An American mechanician has invented a tricycle to be driven by compressed air. The reservoir is an iron tank which forms the seat of the rider; compressed air is pumped into this tank, and the tricycle is (to be) propelled forward at the rate of 25 miles an hour! The inventor proposes to erect "pumping stations in town and country" where the traveller can renew his pneumatic force at a "trifling fee." The dynamo-electric bicycle is quite out of the hunt now.
Passing away now from the inaugural address, we come to those delivered by the Presidents of sections, without some notice of which any account of the Jubilee meeting would be very imperfect. Since these addresses of necessity deal with the same subjects which have been already passed in review, it might be thought a needless task to sketch, even in outline, the course of them. But this is far from being the case. It is quite possible for many to traverse a vast plain without pursuing one beaten track, and indeed without doing more than occasionally cross each other's lines. And so it is here. Each traveller has his own starting-point and follows his own course, and the paths seldom approximate, though all trend in the same general direction. Here and there a subject dismissed by the President in a sentence becomes the text for a whole discourse, or a gap which he himself indicated is appropriately filled. But there is great variety both of topic and treatment, the general tendency being less to historical survey than to scientific exposition, even as the place and the time demanded less of panoramic effect and more of detailed completeness. The addresses were delivered mostly on Thursday, September the 1st.
In Section A., Sir W. Thomson discoursed on the sources of energy in nature available to man for the production of mechanical effect. Summarising the natural sources of energy, as the tides, food, fuel, wind, and rain, he said that of all these there is only one not derived from sun-heat, viz., the first. The utilisation of tidal energy he dismissed as impracticable, owing to the cost of dock construction. Even in the few places where it would be possible to build a sea-wall across the mouth of a natural basin or estuary, it would be more economical to shut the sea out altogether, and make fertile land of the whole basin. Turning to the sources of energy derived from sun-heat, he lamented first the decadence of wind-power, and intimated the importance, nay, the necessity of its revival, especially in view of the exhaustion of the coal-measures, which is sure to proceed at an increasingly rapid rate, until coal ceases to become a marketable commodity. By the aid of the new storage-power of electricity, the continuity hitherto lacking in wind-power might be secured. Cheap windmills were therefore to be regarded as a desideratum of the future. Water-power was next considered. While its immediate action must always be confined to hilly districts, or places where a natural fall is provided, as in waterfalls, the splendid suggestion of Mr. Siemens, as to the electrical transmission of such power to any required distance, opened a great future to this form of available energy. Even the difficulty of the minute subdivision of such energy for practical purposes, which had long operated as a barrier to its introduction, was now being overcome by Faure's invention.
Disregarding for the moment the order of the alphabet, we turn to Mechanical Science, which, as we have seen, was, by the Meeting of 1839, constituted a distinct province of inquiry, under the name of Section G. The opening address was delivered by Sir W. Armstrong, and was of such a character as to demonstrate clearly the kinship of the Section with that from which it sprung. Indeed, on this occasion, the addresses in these two Sections were so similar in texture that either might have been delivered in place of the other. The ostensibly theoretical one was intensely practical, and the ostensibly practical one profoundly theoretical. Yetâ€”and this confirms an observation we just now threw outâ€”though the topics are nearly identical, the treatment is so different as to give the impression that we are going over new groundâ€”a testimony alike to the varied scenery we traverse and to the distinct individuality of the minds which describe it.
The steam-engine is Sir William's starting-point, but his aim is the same, to discover new forms of energy or more economical uses of old ones. The wastefulness of the steam-engine he denounces as monstrous, and after showing from whence it arises, he points out that "unless a method can be devised of burning the fuel inside instead of outside the apparatus, so as to use the heated gases conjointly with the steam as a working medium in the engine, a remedy appears to be hopeless." Already we practise internal combustion in the gas-engine and in the gun. The mention of the last-named machine, with which Sir William's own name is so intimately associated, suggested an observation which provoked some merriment, viz., that though a pound of coal as used in the steamengine produced a dynamic effect five times greater than a pound of gunpowder in the practice of gunnery, yet he did not advocate the substitution of steam for gunpowder in the latter. The wastefulness of the engine thus condemning it, on grounds distinct from the failure of supply, the claims of electricity as a substitute were next canvassed, not without some animadversion on the exaggerated popular estimate of its efficiency. The differences between heat and electricity in their modes of mechanical action were then clearly indicated; and the alternate attraction and repulsion of the latter shown to promise far greater economy than is possible with the expansion of volume which attends the action of the former. If, therefore, we could produce electricity as easily as we can produce heat, the gain would be enormous; but this, as yet at least, we cannot do. Instead of beginning with electricity to produce power, we begin with power to produce electricity. How to obtain electricity, then, seems to be the problem that lies immediately before us. For the purpose of discussing this, Sir William Armstrong enumerated the sources of energy mentioned above, only adding to Sir W. Thomson's catalogue chemical attraction or affinity. Can electricity be derived from this last, as heat now is? Directly, he thinks not; but mediately, through heat, he believes it may. This brings us face to face with the thermo-electric engine, and points to a time when the latter "may not only be used as an auxiliary, but in complete substitution of the steam-engine." The sun's heat was next touched upon, and the want of efficient apparatus for its conversion into electricity shown to be the only hindrance to the availableness of that enormous force, capable in the tropics of melting annually a layer of ice eighty-five feet thick, and consequently of exerting on every acre of soil exposed to its rays the amazing power of four thousand horses for nearly nine hours per diem. The possibilities of the future were thus seen to be boundless. And as Sir William Thomson had wound up with the prospect of science working on the grand scale, and wielding for our good the forces of Niagara, so Sir W. Armstrong depicted her as condescending to serve even our petty individual requirements by securing to us the use of an electric bicycle or tricycle exempt from the labour of propulsion.
The display of Bicycles and Tricycles is also an extraordinarily good one. The progress made in this new industry during the last few years has been really remarkable. The substitution of the wire tension wheel for the old wheel with wooden spokes was the initial invention which rendered so many other improvements possible. The tricycle, which is the most recent invention, is now being used, not merely for purposes of locomotion, but also as a very useful parcels carrier, and several of these machines fitted up for the service of the parcels post, for the conveyance of milk, and the use of retail tradesmen, are shown. Amongst the most recent improvements is the safety bicycle, which is now manufactured by nearly all makers of repute. One type of this machine has comparatively small wheels, to which the motion is imparted by chain gearing, the crank axle being situated very near the ground, and the gearing so arranged that the principal wheel makes about one and a half revolutions for every turn'of the cranks. In another type the cranks are retained on the axle of the principal wheel, but are worked by levers, which arrangement enables the saddle to be placed further back, thus rendering a fall forward more improbable. The Queen's Gate Annexe contains also several fire engines, extinguishers, escapes, and accessories.
Almost the first stand encountered in this part of the Gallery is in the occupation of Mr.J.W.Swan, the inventor of the celebrated incandescent lamp which bears his name. He exhibits the Swan Lamp in various sizes, and applied to various purposes. These lamps can now be had in powers ranging from 2 1/2 up to 100 candles. Amongst them is a small lamp for illuminating the internal cavities of the living body during operations. Mr.Swan also exhibits a new process for the production of perfectly uniform carbons for incandescent lamps. The filaments are produced from a liquid by pressure through a die. He also exhibits an electric meter, consisting of the combination of a galvanometer and a clock, which indicates on dials, similar to those of a gas-meter, the amount of electricity used by each consumer. Close by, Messrs.Laing, Wharton & Down exhibit dynamos, current-regulators, arc lamps, switches and cut-offs. A little way down the Arcade the Consolidated Electric Co. show the B T K system of electric lighting from storage batteries, and of distribution of electricity from a central station for house-to-house lighting. Nearly opposite, on the right-hand side, Mr.G.TrouvÃ© shows his well-known primary batteries, an electric motor, and models of electric boats, and an electric tricycle.On each side of the way, for some distance down, are numerous cases containing various fittings, and appliances relating to electric lighting, telegraphs, telephones, motors, batteries, and dynamos, which are well worth visiting.
ELECTRICITY AS A FACTOR IN HAPPINESS.
Perhaps the most marked feature of the hour, outside politics, is the anxious and hopeful attention paid to applications of electricity. Investigation and experiment have been going on for years, hundreds of minds have given themselves to the subject; in one department, telegraphy, great results have been achieved and great fortunes made; but this explosion of interest in the matter is new. The world, as sometimes occurs to it, is on intellectual tiptoe. The terminology of the science is novel and unusually abominable, the difficulty of showing experiments is considerable, and the reporters constantly misunderstand alike what they hear and what they see; but the interest of the public overcomes every obstacle. At the meeting of the British Association, nothing attracted like electricity, the papers even republishing long discourses which, for most of their readers, might as well have been written in Greek; while no telegrams are read so eagerly as the excessively crass ones in which the wonderful show of electric appliances now going on in Paris is so dully described. The special corrrespondents are shown everything, and not only understand nothing, but seem to lose their control of their art, and cannot even describe. The interest is the more noteworthy because it is the interest of expectation, rather than the interest of assured faith. The electric savants, unlike most men of science, are doing their thinking aloud, performing experiments in public, talking to each other across continents and in the ears of half mankind, showing instruments which they confess are imperfect, exhibiting processes which are acknowledged to be merely tentative, securing patents which are defended as only "precautionary," and in many instances letting drop hints as to the methods by which they are inquiring, and the results they barely hope to obtain, which on other subjects would arouse in their hearers a sense of angry tedium. The public, however, is tireless upon electricity. It has one big fact to go upon, the electric telegraph â€” the one thing, perhaps, which Friar Bacon, if he could come back for a week, and talk to the luminaries of science, would admit to surpass his reveriesâ€”and in spite of the doubts of the scientific, who are excited, too, and see their way to many things, but do not yet see their way to a lot of electric force cheap, the public persists in believing that steam is played out, and that the world is about to have a greater, less cumbrous, and more universally applicable force placed at its disposal. Thousands who know no more what an "Ohm" is than they know what Arius taught are the happier for that belief, and hold it fixedly. The world may be wrong, as it was wrong when it fell into a similar condition of excitement about Montgolfier's balloon. There was the balloon, and it did go up, and better balloons were made, and have been going up ever since from dancing platforms, and besieged cities, and battlefields, and all manner of places; but the world is not flying, for all that, national boundaries have not disappeared, and there are custom-houses still existing. The world, however, this time does not think itself wrong; the scientific men, though not quite certain â€” being worried in their minds, as we said, as to where that cheap lot of force is to come from, unless they can previously accomplish the task of controlling Niagara, or passing the Atlantic tide through a stopcock, or utilizing the earth's rotation â€” are inclined to agree with the world; and the mechanics point, with a sort of awed laugh, half-triumph, half-puzzlement, to what has already been done.
That is really very surprising in its suggestiveness. No electric appliance not intended for the transmission or messages is as yet perfect, or rather, we should say, complete; but still the first idea of impossibility has, in many departments of work, been finally removed, and that is a great step. Electricity â€” we shall want a shorter word very soon, O philologists! and a better one, "amberishness" being a stupid description, and the proper one, if you knew it, would be "Indra" â€” can already be made to do many things, though it does them all imperfectly, expensively, or with a certain uneasy hesitation, as if some Demiurgus did not quite know whether he was justified in giving such power as that to such a race as man, and every now and then held his hand. Man may â€” and man will, if ten more years are given him â€” use his new slave upon his favorite work, the only work he permanently and always admires, that of killing his brothers wholesale; and Demiurgus may be worried about that. Still, electric work is done, and work greater than ringing angry little hotel bells. There is, to begin with, always the telegraph, which does take messages across the Atlantic ahead of time. Then, though the big electric lights flicker and go out unexpectedly, and the little lights are not as bright as they should be, and all the lights are more or less disagreeable in color, and nobody will give you the least dependable hint about cost, and everybody tells a different story about the distance at which the force begins to tire and slacken, there is certainly light, light, if you will pay the money, almost limitless in quantity, and in practice able to go all the distance from the generator that is wanted. And slowly, slowly, but quite visibly, the obstacles to the use of that light pass away. Subdivision, the old difficulty, considered insuperable, has been mastered; a measuring instrument for the light consumed has been invented; yesterday, some weeks ago, the color of light that human eyes find easiest was secured; to-day â€” this very week â€” the flicker has been conquered by an application of Faure's accumulator; and tomorrow, perhaps, the easiest, cheapest, and handiest generator of the force will be shown to a Parisian audience, anxious chiefly to know if with electricity substituted for gas, theatres will not light up very well indeed. There is light, and, moreover, movable light, which seemed impossible. On Monday, while the British Association were discussing the use of the light in mines, and lamenting the chance of explosion at the point where the wire enters the lamp, Mr.Swan produced a lamp which, by the aid of Faure's secondary battery, dispenses with the wire. It will only burn six hours, but it can be carried about, and refilled at will from the wire connected with the central generator. That lamp next year will burn twenty-four hours, and then we have a lamp universally useful for domestic purposes. Again, though no great feat of hauling, or heaving, or pushing has yet been performed by electricity, we know the force can be made to push and haul and heave. A man has driven about Paris in an electric tricycle; a girl has sewn a shirt with a sewing-machine moved by the same power; a bit of rock has been attacked by an electric borer; a toy boat runs about in a lake driven by electricity; and best of all, Messrs.Siemens are now carrying passengers in a "tram," which has no other motor than the electric "fluid," or modification of motion, or whatever it ought to be called. It is not only probable, but certain, that many of the difficulties now impeding the application of the force to heavy work will be dissolved, under the pressure of the brainpower now applied to them from every corner of the civilized world; and quite possible that in a year or two a cheap method of generating electricity will be applied â€” not discovered, for we know already that falling water, in governable masses, is what is wanted â€” and that the storage of the force will not only be a credible, but an easily accomplished, process. That is not supposing more than has occurred in the application of electricity to message-sending, and that accomplished, and cost reduced, as science always reduces it, we should have from the new agent at least two things â€” a light, full, permanent, and cheap, to be used wherever wanted, in the street, work,shop, and house, as in the mine; and a motor, manageable, tireless, light, and as effective for small work in the hands of the individual as for great work in the hands of a mighty company. That which will drive a railway train will drive a girl's sewing-machine or a boy's mechanical horse, that which will urge a rock-borer will help to carve a sixpenny bloodstone seal, lndra chained can be made to perform all tasks that can be performed by unintelligent force.
And these things gained, what will be the addition to human happiness? It is always necessary to ask that question, for, as a rule, the grand prizes of human intelligence, the additions to human knowledge of which we are so proud, have added little to the happiness of the millions who, and not the few rich, constitute man. The growth of wisdom, especially of political wisdom, has probably, by abolishing slavery and diminishing terror, whether proceeding from kings, or armed enemies, or domestic criminals, done more to increase the happiness of the race than all that science, usually so called, has ever achieved. Freedom from oppression has secured more for Englishmen, measured directly in happiness, than steam, just as security from robbers has done more for their wealth than the electric telegraph. It would be difficult, indeed, to prove that any great scientific discovery, â€” except the lucifer-match, which made light and heat, as it were, portable, chloroform, which extinguished some forms of pain, and vaccination,â€” has ever done very much to reduce the mighty sum of human misery. There would seem, however, if all hopes be justified â€” even excluding these hopes raised in a somewhat dim way by Dr. Siemens' strange experiments with plants, experiments which somehow raise in minds not usually fanciful a sort of sympathy with plants, as if they must suffer, instead of benefiting, as they appear to do, from the sleeplessness to which he condemns them â€” to be good omens for man in electricity. Light in the bowels of the earth, permanent, pellucid, and safe, must indefinitely diminish the terror and the toil of those who work there, even if it does, as we fear it will, protract the hours of labor; and miners of all kinds are many, and we want more from inside the world. Bright light, indeed, if it can but be earned about, must relieve man at least of the terror of darkness; and terror, not pain, is for humanityâ€”which is in the aggregate timid, but healthy â€” the master evil. Then it would seem probable that in electricity we have a motor which will do what steam has not done, add to the strength and freedom of the individual; and that must be a gain. The instinct of luxury is rarely wrong when it is permanent, and the desire of the rich for horses and carriages must, if realized by the poor, increase their happiness. Rushing about is not happiness, but freedom of locomotion is an element in it, and in the electric tricycle there is a probability of that for all healthy men. The power of working a machine which will do almost all labor must be, one would think, to man again almost equivalent to increased health, or a doubled strength of muscle. The peasant may have no more land, but the electric plough will do his spade-work as well in less time and with less expenditure of vital energy â€” for of all classes, it is not ploughmen who live longest, as, in the idyllic theory, it should be, but gamekeepers and clergymen â€” and the additional force gained in agriculture will be gained also in every department of human labor, the weaver guiding without stooping an electric loom, while the shoemaker orders the fluid to perfect his stitches. Electricity is force without the limitations which make cumbrous steam comparatively so useless; and if anything can make man happier, except more resignation, it must be an increase of force granted to every one for the battle with the blind powers of earth, which yield only to compulsion his food and drink.
ELECTRICITY FOR THE TRICYCLE.
Electricity has long been threatening to displace gas as an illuminant. It is now entering the field against the horse as a means of traction. Two eminent electricians claim to be able to bottle up twelve horse-power in a storage battery weighing three hundred weight, and they promise to produce in a few months a perfectly practical electric tricycle, capable of running fifteen or twenty miles without recharging the accumulators, and able to ascend all such hills as are now possible for the foot tricycle and even steeper gradients if auxiliary foot gearing be used to help the electromoter when the incline is great. The weight of batteries will not exceed the weight of a second rider, and it will run at the rate of seven miles an hour. As the new motor will never go lame or shy or break its knees, or eat its head off when not employed, it is likely to prove a dangerous rival to the horse. The quadruped, however, which has survived steam need not fear extinction by electricity.â€”Pall Mall Gazette.
Electric Tricycles.â€”An attempt is being made in England, in a modest way, to utilize electricity as a motive power for tricycles, the prospectus of a company having been issued. It is proposed that 103 persons bind themselves to buy an electric tricycle at $250, or, in other words, that shares of $250 each be issued, each holder of a share being entitled to be supplied with an electric tricycle. The first machine to be produced is an electric tricycle carrying two persons and fitted with battery and motor sufficient to propel it on level ground at the rate of six miles an hour.
ELECTRIC LIGHTING AND LOCOMOTION.
Forty-three years ago it was practically shown by Jacobi, on the River Neva, that locomotion by the aid of electricity was possible. No experiment, then, merely to prove this fact is needed at the present day. Nevertheless, both experiments and calculations are still necessary to convince the world that electric locomotion is not only possible but also commercially practicable. That electric transmission of power possesses great advantagesâ€”arising, first, from the small weight of the electromotor per horse-power developed by it; secondly, from the fact that large amounts of power can be transmitted through quite thin flexible wires must also have struck any one who has ever seen a powerful machine driven by electricity. Its disadvantages are generally summed up in the single sentence that it is too expensive. But people, as a rule, do not trouble themselves to inquire whether it is really more expensive than other modes of transmitting power, and whether, if this be the case, it arises from some inherent defect in the principle itself, or merely from some removable imperfection in the maohinery hitherto employed for the purpose.
At the present day the public may be divided into two classesâ€”the one who thinks that electric locomotion and transmission of power will act as a sort of philosopher's stone, and solve all difficulties; the other, that it is a new fangled notion, and carefully to be shunned. Tho first class implores to be allowed to buy shares in any company that can in any sort of way have the word "electric" tacked on to its title, while the other buttons up its pockets at the mention of the word electricity, and busies itself with what it terms "something useful and practical." And, unfortunately, the repeated failures of the sanguine members of the first class to reach the El Dorado they have imagined to themselves only strengthens the belief of the more cautious members of the second class in their shrewdness aud in the wise decision they fancy they have arrived at, that electricity is a mere will-o'-the-wisp.
But you, I am sure, will not have that opinion when you have seen tonight what can be done by electricity. I turn on this electric tap, and at once this fan commences to revolve rapidly, and sends forth a rush of wind. That, perhaps you will say, could as well be done by a belt driven by a steam engine; but I turn on another tap in the same supply wire, and at once the fan is lighted up by this electric lamp. That could not have been done merely by a steam engine. Again, a third tap; this electric fire burns, and the water starts boiling in this glue pot. [Experiment shown.] This thin flexible wire then furnishes a supply of electric power which can at will be used for producing motive power, light, or heat.
Now, to produce this supply of electric power, we must first have a steam engine, a gas engine, a water-wheel, or windmill to produce motion, and a dynamo machine to convert the mechanical energy into electric energy. These may be in the same room, or in another part of the building, or in another street, or away in the country; the electric power may be brought by a wire and used directly, or it may be stored in Faure-Sellon-Volckmar accumulators and used at some subsequent time, as I am doing now, thanks to the courtesy of the Electric Power Storage Company. Indeed, I may mention that in all my experiments I am using only stored electricity; and in this room, where we are utilising this supply of electric power, we must have an electro-motor if we want motion, an electric lamp if we want light, and an electric fire if we want heat. The transmission of power by electricity seems, then, very useful. Can it be made commercially remunerative?
As there are, doubtless, many in this hall who are deeply interested, either from scientific or from commercial reasons, in the answer to this question, and generally in the practical applications of electricity, it will be well to commence this lecture by considering, as shortly and as popularly as possible, what are the real difficulties besetting electric transmission of power, and what are the means electric engineers aro proposing for surmounting them. Let us then attack the question together, not in the rosy, sanguine humour of the promoters of electric bubble companies, nor with the cold, hard scepticism of those who forget that with the early locomotive engines the fireman had to run along the road by the side and stoke, but as common-sense Englishmen who are anxious to know whether at the present moment the pros or the cons are in the majority.
An electric current, as you have seen, can produce heat; but, unfortunately, not only can an electric current produce heat, but an electric current always is producing heat. Now, while it is very proper that heat should be produced in an electric lamp or furnace, it is quite out of place in the dynamo machine or generator of electricity, or in the leading wires, or in the electro-motor, which converts the electric energy into mechanical energy. In all such cases the heat produced by the electric current corresponds with the heat produced by friction in machinery, and causes the same sort of waste of power.
But this loss of power, we shall see, is not necessarilv so very great even when the power has to be transmitted a considerable distance for when there are a number of machines, lamps, or motors that have to be worked by electricity there are two ways in which they may be connected together. They may all be joined in what is technically called "parallel," or they maybe connected in "series." In the first case the current (as was illustrated by diagrams) that passes through any one of these machines does not pass through any other, and the generator must produce a large currentâ€”as large, in fact, as the sum of all the currents passing through all the machines. In the second case, the "series" arrangement, the same current of electricity passes through all the instruments one after the other in succession, and the generator only produces a current equal to that passing through any one of them. The ordinary methods of supplying houses with water or with gas are examples of the parallel system, because the water or gas that is supplied to any one house does not go to any other. The postman brings the letters and the boy leaves penny papers at a number of houses in parallel, while a copy of The Times, lent out at a penny an hour, is furnished to a neighbourhood in series.
And just as a newspaper or a book from a circulating library loses in freshness, although gaining in thumb-marks and dog-ears, when supplied to its readers in series, and as water loses head or pressure as it flows down astream, so electricity loses its potential or power to work in passing through a number of machines worked by it in series.
To work, then, a number of electric motors or lamps in the multiple arc system we must at starting supply a large quantity of eloctricity at, it may be, only a low potential or pressure; whereas, if they are joined in series, the current may be small, but the initial pressure must be great.
In all electric railways and tramways constructed up to the present time the multiple arc system has alone been adopted. This you will see from the photographs that I will now project on the screen of all the most important electric railways yet constructed. First comes three photographs [Photos, on screen] of the small circular railway, 900 yards long, of 3ft. 3in. gauge, laid in the grounds of the Berlin Exhibition in 1879, and exhibited in 1881 at the Crystal Palace, Sydenham; next, a photograph of the Lichterfelde Railway, near Berlin; then the electric tramway in the Champs Elysee, Paris; and that of Charlottenburg, near Spandau. The latest electric railway, the one six miles long, now in course of construction at Portrush, near the Giant's Causeway, in Ireland, I shall reserve, as I shall have much to say about it later on in these lectures.
[Photographs were then exhibited of the various electric railways, which were described in detail]
But the amount of power lost in heat when a certain definite amount of power is being transmitted through a given wire is very different, whether the multiple arc or the series system be adopted, because the heat produced per minute depends on the strength of the current used in the transmission and not in the amount of power transmitted. Indeed, it depends not merely on the current, but on the square of the current, so that if the current be doubled the waste of power becomes four times as great as before. Economy in electric transmission, therefore, requires small current, and, if much power is to be transmitted, small current necessitates high potential and the motors or lamps working in series. Similar considerations apply to the transmission of power by water: to obtain great economy high pressure is absolutely necessary. The accompanying tables, taken from Professor Perry's Cantor Lectures, show the amount of loss of power when different amounts are transmitted different distances by water at an united pressure of 700lb., and at 1,400lb. per square inch, as well as the amount lost when electricity is employed with a difference of potential between the terminals of the dynamo, first of 8,000 volts, secondly of 80,000 volts.
But high electric potential or pressure is generally considered to mean danger to life, and series working of machines or lamps has this disadvantage, that if from any accident the current is stopped passing through one it is stopped passing through all.
The danger arising from the use of high potential can be very much diminished if, instead of using the earth as part of our return circuit, we employ not only an insulated wire to convey the current, but also another insulated wire to bring it back again, and if in addition the current flowing through the whole circuit is not intermittent. This may be shown by the following experiment: Attached to these wires, well insulated from the ground, are the insulated coatings of this battery of charged Leyden jars. Now, although the difference of potentials between the wires is some thousands of volts, far, far greater than is at present used, or proposed to be used, in any system of electric transmission of power, I can, as you see, touch either wire with perfect impunity. But if either of these wires be replaced by a wire in contact with the earth, say replaced by one of the gas pipes, aud I were now to touch the other, I should receive a violent shock.
As, however, my love of electric experiments does not extend to shocks, I will touch the insulated wire by deputy, using this metallic rod, and the result is, you see, a bright spark. [Experiment shown.] Both the going and return wires, therefore, should be insulated.
But, next, the current flowing in them must not be discontinuous if danger is to be avoided. For if, instead of keeping the difference of potentials between any two points in the two insulated wires constant, I allow rapid fluctuations in this difference to take place, then, no matter how well the wires be insulated, a violent succession of shocks will be received on touching either of the wires, even although the other be not touched, so that no circuit in the ordinary sense is completed through the body. To show this experimentally I shall replace this insulated battery of Leyden jars with an induction coil, which, as well as the voltaic cells used in charging it, are thoroughly well insulated from the earth in every part. Let me, however, touch either of these wires -again by deputyâ€”and you see bright sparks passing to tho earth. [Experiment shown.] Bear in mind that I am touching one wire only, not both, so that, although the Ruhmkoff coil is doubtless an old friend to you, I am using it to-night in a new way to illustrate my point.
Now let us consider why it is that when a current goes and returns by a wire completely insulated from the ground no shock is experienced when the current is perfectly steady, even if a bare part of the wire be touched; but if there are rapid variations in the current strength severe shocks are felt even if only one part of the wire be touched.
In each case the effect of touching the wire is to reduce the potential of the point touched to that of the earth, and to effect a corresponding alteration of tho potential along the whole line. This means the addition to a subtraction of a certain quantity of electricity from the wire. In the case of a perfectly steady current this operation only occurs once for once touching the bare wire, and unless the electrostatic capacity of the wire be very great, or the potential of the point touched immensely different from that of the earth, this single addition or substraction of electricity produces hardly any perceptible feeling. But in the case of a varying current the potential of the point would naturally be undergoing constant variations of potential, so that in order to keep the point touched at the same potential as that of the earth, constant additions and subtractions of electricity are necessary, and if these occur with sufficient rapidity a severe shock is produced, even although the body forms no part of the main circuit.
A single puff of air through this syren produces no audible sound, a rapid succession of even minute puffs a loud roar; so the single small electric discharge is not perceptible, but the rapid shower of Lilliputian arrows is terribly painful. This, indeed, is the same analogy Professor Perry employed in his lecture at the Society of Arts to prove the powerful action of rapidly recurrent effects in connection with our method of signalling to ships by means of sound waves sent through the water.
High potential, I have explained, is absolutely necessary for economy in electric transmission of power, and I hope I have also made it clear to you that, contrary to the received opinion, this high potential is not necessarily at all dangerous to life if the currents employed are not at all discontinuous. But the discontinuity of current we have to deal with is not merely the discontinuity that exists in the so-called reverse current machines. Even many dynamos, like the Brush, do not produce a really constant current, although generating a current of sufficient mean constancy to cause a perfectly steady deflection on one of the ordinary ammeters of Prof.Perry and myself, an instrument, be it remembered, so dead-beat that it records with perfect accuracy the change of current produced every time the joint in the driving-belt passes round the pulley of the dynamo, as well as the regular increase of current at each of the explosions of the gas in the cylinder of a gas engine.
The variations of current I am now referring to occur many hundreds of times a minutes, and although they cannot be detected by ordinary current meters, and although but little attention has been given to them, they are, in my opinion, a source of great danger when the dynamo produces a high electromotive force.
In any machine for the mechanical production of electricity a coil must, as you no doubt all know, be alternately rapidly brought up to a magnet and then withdrawn. Bringing up the coil produces a current in one direction in the coil, and withdrawing it a current in the opposite: and although by a simple piece of mechanism, called a commutator, the direction of the current in the external, or useful, portion of the circuit may be always kept the same, even although the direction of the current is alternately reversed in the coil no mechanism can make the coil produce a current at the moments of rest, when it changes its direction of motion. Wheatstone, in 1841, proposed to overcome this difficulty by combining two or more dynamos in series, like the two cylinders of a steam engine, in such a way that the current produced by the one was strongest when the current produced by the other was weakest; but Pacinotti, in 1860, showed us scientifically, and Gramme, in 1870, practically, how to combine a number of moving coils in one machine so as to give a current comparable in steadiness with that produced by a voltaic battery. The power of any dynamo depends roughly on the speed at which the coils move and on the strength of the magnetic field in which they move. Now, from the construction of the well-known Gramme machine, the strength of this magnetic field is necessarily weak when the machine is made of large size so that the greater power and efficiency which ought to come from enlarging the machine is partially compensated for by the relatively weaker magnetic field: indeed, even in a small Gramme machine the magnetic field is probably weaker than the magnetic field produced long ago in the old reverse-current machines of Holmes and Wilde. Hence more recent inventors, like Brush, have adopted a compromise between the perfect uniformity of strength of current obtained with the Gramme dynamo and the strong magnetic field in the old reverse-current machines. But in almost all the high electromotive force dynamos continuity of current has been somewhat sacrificed to strength of magnetic field. The plan, however, described in 1879 by Professor Perry and myself of oblique coiling of the armature, has enabled us, especially in our recently-constructed machines, to combine the continuity of current produced by a Gramme with the powerful magnetic field necessary for obtaining high electromotive force, and these results are in no way diminished when the machine is increased to the size necessary for utilising hundreds or thousands of horse-power and for obtaining that high efficiency which both theory and practice show is obtainable with the use of very large dynamos.
The next point to consider is how can we measure the amount of this dangerous discontinuity in the current produced by a dynamo without having to resort to the inconvenient process of killing off a certain number of people. We want a "discontinuity meter," and such an instrument I have here, employed by Professor Perry and myself for this purpose. It consists simply of an induction coil in which both the primary and secondary circuits are of thick wire. The one is put in the main path of the current, the other is attached to one of our "Spring Ammeters," which measures the mean square of the strength of the reverse currents produced in the outer secondary coil by the intermittencies of the main current.
Now, what are the results obtained when such an instrument is practically employed? Why, we find that when a current of ten amperes, produced by a three-light Brush dynamo, is flowing throngh the primary, there is a reverse current through the secondary which increases to about five amperes, when the secondary is nearly short-circuited, and which, be it remembered, is produced merely by the commonly ignored discontinuities in the current in the main current produced by the Brush machine. On tho other hand, when the same current, ten amperes, is sent through the primary by a Gramme machine running at about the same speed, no visible current, certainly not a quarter of an ampere, is produced in the secondary. Hence it is clear that the continuity of the Gramme current is immensely greater than the continuity of the Brush current.
A telephone may also be used as a discontinuity meter, the two terminals of which are in different experiments attached to two points close together in the main circuit of the dynamo. For quantitative experiments these two adjacent points in the main circuit should be selected, so that in all cases there is the same difference of potentials between them, and then the pitch of the note heard in the telephone will tell the number of variations per minute in the main current, and the loudness of the note the magnitude of such variation.
And I strongly advise any one who is procuring a high electromotive force dynamo to ascertain for himself, before purchasing, the magnitude of the discontinuity factor of the machine, and about which he will find no information, as a rule, given in any description of the machine.
The other inconvenience arising from the use of high potential and small current, viz., that as the motors and lamps must be put in series the accidental stoppage of the current passing through one stops the current passing through all, is easily remedied by the use of what are technically called "cut outs." A cut out, as you see, consists of an electro-magnet wound with comparatively fine wire, and which allows a small part of the total current to pass throngh it instead of through a particular motor or lamp. If, however, from no failure in the generator, no current can pass through the motor or lamp, then more passes through the cut out, the electro-magnet of which becomes stronger than before, attracts the armature which closes this side circuit, and so allows all the current to flow by the bye-pass thus formed.
We have seen, then, that for economic electric transmission of power high potential must be used; secondly, to avoid danger to workmen and others likely to touch the wires, both the going and return wires must be insulated, and also the current must not only be what is practically called a constant current, but must not be subject to the rapid variations in intensity such as are produced by many existing dynamos.
Next, in a satisfactory system of distribution of power, be it electric or otherwise, the supply should be exactly equal to the demand;a greater or less demand for power on the part of any consumer should not be accompanied by a less or greater supply to any other consumer of power. In the distribution of gas to a town this problem has never been completely solved. Owing partly to the mass possessed by the gas in the mains no automatic regulator has over yet been devised to use at the gas works so perfect that our burners do not flare at about nine o'clock in the evening, when the consumption of gas in the town is being rapidly diminished; and, indeed, at the present day a gas engine in a building even fed direct from the main will cause unpleasant pulsations in all the lights in the same building, also fed directly and separately from the main, so that the number of explosions in the gas engine can be counted all over the building. The pressure regulator at the gasworks cannot act quickly enough, so that Sugg and others have devised automatic regulators to attach to the burners themselves in the houses.
Constant pressure in the case of gas corresponds for electric lamps or motors in parallel, with constant difference of potentials between the leads and with constant current for lamps or motors in series.
As an illustration of the importance of these considerations you see this battery of three Grove's cells will light this incandescent lamp, or it will drive this electro-motor, but when I attempt to unite them in multiple arc together, the light of the lamp is, you observe, much diminished in intensity, due to the fact that the difference of potentials at the ends of the carbon filament is diminished when the motor is started. Again, I have those two lamps in series; I now allow the current to pass through a third lamp in the same series, and you observe that all the three are duller than either were before, due to the current being diminished. [Exp. shown.]
And, conversely, if from a sudden diminution in the consumption, arising from many of the lamps being suddenly turned off the difference of potentials between the main wires is much increased, all the remaining incandescent lamps are suddenly broken. Indeed, when the governing of the difference of potentials or of the currents was much less perfect than at present, it was no uncommon thing for hundreds of incandescent lamps, costing many pounds, to be suddenly broken.
Consequently, the problem of supplying either constant difference of potentials in the parallel system, or constant current in the series system, independently of the consumption of electric energy, and which might at first sight appear rather a dry and uninteresting problem, is in reality of great practical importance, since it must be solved before one train on an electric railway shall not suddenly start going faster because another has stopped, or before the electric lights in one train shall not become dim or break because the passengers in another train have turned theirs on or off. It is a problem, therefore, to which electrical engineers have devoted much attention during the past few years.
In my last lecture, I explained why small current combined with great electric pressure or high potential must necessarily be used for economy in electric transmission of power, and why, therefore, the series working of lamps and motors was better than the parallel system. I went pretty fully into the consideration of what was necessary to obtain safety, and we found experimentally that two conditions were essential: the first, that both the going and the return wires should be well insulated from one another as well as from the earth; the second, that the current should be absolutely constant in its strength, and not merely have the mean constancy obtainable with many of the so-called constant current dynamos.
The very important problem of supplying constant electric pressure to the mains, however many lamps or motors were being fed by them in parallel, was next considered, as well as the problem of supplying constant current to motors or lamps in series, however many lamps or motors were being worked in one circuit.
We ended by considering the great importance of driving quick moving tools like drills, fans, circular saws, &c, directly with electro-motors without intermediate gearing, because with such arrangement we saved first the loss of power that occurs in the shafting of a factory; secondly, the loss of power at the intermediate gearing employed to make the drill, or other quick moving tool, revolve much more rapidly than the shaft, and, lastly, we secured the great convenience of being able to bring the machine-driven tool to the work, instead of, as at present, the work to the tool. And there is one case where the driving of fans by electro-motors appears to me to be at the present moment of vital importance to us as citizens of London, I might almost say of national importance to us as Englishmen. For years past we have gone on breathing the foul air in the underground railway. Much grumbling has been the result, but hitherto no ventilation, and at the present moment we are contemplating, as a sort of final resource, the possibility of unsightly openings being made in the roadway of the Embankment to let out the obnoxious gases. Now why, I ask, do we not put fans at suitable intervals along the tunnel attached to quite small pipes for extracting the bad air? The fans could not, of course, be driven by steam-engines (there are steam engines enough in the tunnel already), nor could they easily be driven by shafting or belting, but an electro-motor attached directly to each fan would furnish the driving power without introducing any inconvenience whatever. No gearing would be necessary, a single insulated going and return wire would convey from motor to motor the electric power produced by a large dynamo outside the tunnel, and a steam engine might puff away in some back yard, out of everybody's way, and give us perfect ventilation on the underground railway.
And when on the subject of electro-motors, I explained that Professor Perry and myself had been led to construct electro-motors on a different principle from that usually adopted. In a dynamo machine there are two electro-magnets, and the machine acts as a producer of electricity because the work that is necessary to be done to move one of the magnets relatively to the other to overcome their attractions and repulsions is turned into electric energy. In practice one of these electro-magnets is usually kept at rest, while the other is in motion. In one of them the current always flows in the same direction, while in the latter it is constantly being reversed in direction. The former is called the "field " or inducing magnet, while the latter is the "armature." Now, it can be shown that in every dynamo-machine the magnetism produced by the current flowing round the armature must necessarily weaken the magnetism produced by the current flowing round the field-magnets, and hence must necessarily diminish the power of the dynamo.
Hence the best dynamos have been so designed that while the exciting electro-magnets form a very strong magnet the armature only produces a very weak one. This result has been arrived at partly by making the armature of a dynamo small, compared with the field electro-magnets, and partly by giving it a squat form; and because the field-magnet is large, it is, as a rule, kept stationary, while the armature revolves inside its poles.
I went on to explain to you that Professor Perry and myself had concluded from certain theoretical and practical considerations, that in an electro-motor, on the contrary, the strengths of the two magnetic fields produced respectively by the field-magnet and by the armature should be equal, since the one, so far from weakening the other, can be made to strengthen the other, and since the armature from its shape is necessarily rather a weak magnet, whereas the field, or exciting magnet, from its shape is a strong one, that we had reversed the usual condition of things, and made the armature large and the field-magnet small, and that from this we had been led to make the armature stationary and surrounding the field-magnet, instead of, as is usual, the field-magnet surrounding the armature.
Our small field-magnet, then, carries the brushes and revolves inside the stationary armature, the coils of which are joined to the stationary commutator, which, unlike ordinary commutators, we make flat to save both space and expense.
Wherever the brushes happen to be at any particular moment, there two opposite magnetic poles are produced on the armature. As the brushes run round and round so do these poles, and the brushes, which, be it remembered, are carried by the field magnet, are so set that the magnetic poles in the armature are always a little way in front of those in the field-magnet. The latter, therefore, are perpetually running after the former, but never catching them.
The law connecting the power of electro-motors with their size I dwelt on, and I explained that if the length, breadth and height of a motor be doubled, so that its weight and cost becomes eight times as great as before, its power is about 20 times as great as before, and its efficiency or the ratio of useful power given out to electric power put in is also much increased.
I ended my lecture by referring, but from want of time only very briefly, to the governing of motors. An ordinary ungoverned motor goes very much faster when running empty than when there is a load on, but in practice it would never do for a piece of wood or iron in a lathe to rush round when the chisel was taken off, since not only would there be a great waste of power, but on next applying the chisel it would be probably broken by the wood or iron when rotating with such an excessive velocity. Not only, then, must we arrange in the way I described, that the supply of electric power is proportional to the demand, but also that the motors consume this power in proportion to the work they have to do; in other words, the electro-motor must be governed so as always to run at the same speed, whatever amount of work it may happen to be doing. I referred to the oldest form of governor for motors, which I have called the "spasmodic governor," and which I will now show in action. [Experiment shown and full explanation given.] The great objection to it is that it either supplies full power when the motor is running too slowly, or no power when it is running too quickly, and, therefore, cannot produce a constant speed. Our "periodic governor," which never supplies full power or no power, but always an amount of power exactly in proportion to the demand, I very briefly referred to, and which I will now describe to you more in detail [Ayrton and Perry's "periodic governor" shown in action and fully explained]; and, lastly, I referred to the most advanced system of governing motors, which we had arrived at by winding the motor with two distinct circuits in such a way that the current passing through one of them magnetises the iron, causes the machine to act as a motor, and, consequently, is itself resisted, whereas the current passing through the other circuit tends to demagnetise the iron and stop the motion, and, consequently, is itself helped on; in fact, we have combined a motor and a dynamo in one machine, and so have dispensed altogether with anything of the nature of a mechanical governor. In the spasmodic, as well as in our periodic governor; the regulating action is produced by the supply of power being cut off when the motor is beginning to go too fast, but in our combined motor it is usefully employed to reproduce electric energy, which is added to the supply in the main circuit. In the one case, when less work has to be done by the motor, less electric power is given it, while with our combined motor the supply always remains the same, but when much work has to be done by the motor, nearly all the electric supply is turned into useful mechanical work; whereas, on the other hand, when little mechanical has to be done, a portion of the supply, after being turned into mechanical work, is re-converted into electric energy, and added to the supply going to other motors. The difference in principle is of this nature â€” the periodic governor corresponds with a man who, when he has not much work to do, does not eat much, lives economically; in fact, whereas our combined motor corresponds with a man who always eats the same amount every day, but when he has little work to do on his own account, immediately goes and helps somebody else who is hard pressed with work. [Experiments were then shown with the combined motor, and it was proved that the change of load which diminished the speed of the ungoverned motor from 1,560 revolutions per minute to 508, only reduced the speed in one of Ayrton and Perry's governed motors from 1,250 to 1,181 revolutions per minute.]
But we find that it is not even necessary to wind the motor with two distinct circuits in order to obtain a certain amount of governing, and this arises from the fact that our machine will act as a motor without any winding at all on the revolving field-magnets. Here is an example of such an unwound motor. I pass a current through it, and it at once commences to revolve, and, as you see, revolves rapidly. [Experiment shown.] This arises from the fact that the magnetism in the stationary armature induces magnetism in the iron of the field-magnets, and the brushes are so placed that the magnetic poles in the armature are always just in front of those in the iron, which latter are always running round and round after those in the former, but never catch them up.
In some of the early electro-motors pieces of soft iron moved in the neighbourhood of stationary electro-magnets, but in that case the continuous motion of the iron was maintained in a totally different way from that employed in our unwound motors, because in those older motors a piece of iron was pulled towards a stationary electro-magnet, opposite which it would have stopped, but that just as it was approaching the end of the electro-magnet the current was stopped and the iron went on by its own momentum; the pulls were therefore intermittent and not continuous, as in the case of our unwound motor.
Now, suppose we have one of our motors adjusted to run without any winding on the field-magnets, and imagine we wind the field-magnets in such a direction that the motor would tend to turn in the opposite direction when a current passed round the coil wound round the field-magnets, what would happen? Why, if the magnetism induced in the field-magnets by the current flowing round it were stronger than the opposite magnetism induced in the iron by the armature, we should have the very curious and novel result that the direction of the motor could be reversed by simply short-circuiting with a thick piece of wire, the current flowing round the field-magnets, and this result we have practically attained, as I will now show you. [Experiment shown.] Allow the current to flow through the armature and field-magnets, and the motor runs one way; let it only flow through the armature alone, and the motion is instantaneously reversed. Merely pressing down the key then reverses the motion. Hitherto the much more complicated arrangement of reversing the electric connections between the armature and field-magnet has always been thought necessary to reverse the direction of motion of a motor.
We have in the preceding considered that the magnetism produced by the coil on the field-magnets was greater than that produced by the induction of the armature itself, and so determined the direction of motion. But suppose that is not the case, then what will happen? Why, then the current passing through the coil on the field-magnets will be resisting the motion, and so will be helped on. But that, as we saw before, is exactly the condition necessary for governing. The armature then and the iron of the field-magnets acts as a motor, while the armature and the coil wound round it act as a dynamo, and if the resistance of the coil, which we make of fine wire, and as a shunt to the armature, is of proper resistance, and the required speed of the motor is the critical speed of the dynamo, the governing of our motor may be made fairly perfect with only one circuit on it.
Hitherto we have been dealing with motors especially intended always to run at one speed whatever amount of work they might be doing. We next come to motors for electric tramcars, tricycles, &c., designed to run at any desired speed forwards or backwards.
I have spoken about the set of the brushes relatively to the field-magnet, and the set, or "lead" as it is technically called, is of great practical importance, since on the amount of lead depends which way the motor revolves or whether it revolves at all. Although the fact that the direction of rotation could be reversed by a sufficient change in the lead was well known, the importance of varying the lead in motors for different speeds appears to be little attended to, since it is impossible as a rule in motors, from their construction, to make small changes in the lead. In our motors, on the other hand, the flat brush-holder can be revolved forwards or backwards by hand through any angle, so that any lead forwards or backwards is obtainable, and in our larger motors, of which I have a sample here, the lead can be made anything we like simply by moving a handle, such as a locomotive engine-driver is accustomed to use for acting on the link-motion of his engine. In fact, by moving the handle forwards or backwards any speed, in either direction, is obtainable. We can, even when the motor is running, shift the brushes relatively to the field-magnet together with which they are rotating, and consequently with only one pair of brushes to give any lead forwards or backwards we desire. In other cases we alter the lead by means of a wheel and screw, and so get very easily a very accurate adjustment. A table of speeds can be engraved, showing the position the handle should be in for 500 revolutions a minute, or 700 revolutions a minute, &c.
On the last occasion I showed you photographs of all the principal electric railways, and we saw that in some cases the current went by an auxiliary insulated rail passed through the motor under the train, and came back by the rails. In other cases both the going and return wires were of the nature of stout overhead telegraph wires, and a running connection between the motor on the tramcar and these wires was kept up by two small jockeys that were pulled along the telegraph wires by wires attached to the tramcar. In a third system, the going and return conductors were simply ordinary rails on which the train runs, the insulation produced by the rails merely resting on wooden sleepers having been found sufficient for a length of one or two miles. As you will see from the photographs that I now project on the screen, this last and simplest plan has been adopted for the Portrush Railway, near the Giant's Causeway, in Ireland. This electric railway, Mr. Traill (the chairman) has been so good as to write to me, "runs on a footpath, or trampath, by the side of the road, which has been widened for the purpose from 24ft. to 27ft. The path is 7ft. wide, leaving 20ft. for the carriage-way. "We first tried," he says, "sending the current by one rail, returning by the other rail, after passing across by the car, and for this purpose had laid the rails in asphalte with thick felt underneath, but we found that the leakage, especially in wet weather, was too great to justify us in continuing that kind of insulation for six miles." Now, this is exactly the result I predicted in my lectures on electric railways delivered last year, and in order to make the difficulty quite clear to you, I will show you the experiment I then showed to prove this. A portion of the going wire conveying the current working the motor is driving the circular saw, as you observe, wrapped round this bit of wood, and a portion of the return wire round this other piece of wood. As the two pieces of wood are dry there is very little leakage from the wire on the one to the wire on the other, although the wire wrapped round each is bare. If, however, without allowing these pieces of wood to touch one another, I immerse the ends of them in this vessel of water I shall produce the same effect as if a shower of rain fell at one end of the electric railway. Now, observe what happens, the motor immediately begins to go more slowly. Let me immerse them further, which will correspond with the rain becoming more general over the line, and the motor goes still more slowly, and now the motor stops altogether, so much of the current, in fact, leaking from the going to the return wire through the water that sufficient does not pass through the distant electro-motor to keep up its motion.
How, then, has this difficulty been overcome at the Giant's Causeway? Mr. Traill's letter tells us. He says :â€”" We have therefore placed a third rail of iron on wooden props close into the fence, so that a brush striking out from the car on a steel bar runs along the top of this third rail, which is about 15 inches from the ground." He goes on to say that this third rail is embedded in tar on the tops of the posts, and that when, in addition, pieces of the new insulating material (" insulite") are introduced between the rail and the wooden posts they expect the insulation will be perfect. He adds :â€”" At present we can run for over two miles on the road up and down hill gradients as great as 1 in 35. We took six tons up that incline the other day. We are about to erect turbines at the waterfall above Bushmills, which will give us from 60 to 100 horse-power, and will generate the current there about half a mile from our main line at Bushmills. We have powers by our Act of Parliament to construct a railway from Bushmills to Dervock (inland about seven miles) almost at right angles to the line of tramway on the sea coast. As the waterfall is near the junction of railway and tramway we intend to use it for the railway as well, as the works will do for both. We are limited by an Act to 10 miles an hour on the tramway, but will have no difficulty in going to 20 or 26 miles an hour on the railway, which has also the advantage of being level the entire way."
But although they have succeeded at Portrush in overcoming the difficulty of leakage by using this third insulated rail, resting on posts 15in. above the ground, such a system presents, you will easily see, great inconveniences for ordinary railways, since at every crossing there would be this raised rail in the way of the trains, and an even greater objection is the risk that it introduces, that any one can, from carelessness or malice, by resting, say, a crowbar against this raised insulated rail, send all the electricity to the earth and so cut off all electric power from all the trains either in front or behind.
On the other hand, the plan of using stout telegraph wires, with running jockeys to keep up continuous electric connection between these wires and the moving train, would present great mechanical difficulties if the trains were going at 60 miles an hour.
What, then, do we propose? Professor Perry's and my plan is this: we electrically subdivide the rubbed rail into a number of sections all fairly, but by no means perfectly, insulated from the ground. We do not apply our electricity directly to this rubbed rail, but instead, to a well-insulated conductor, which may be buried underground or may be insulated by resting like a telegraph line on insulators or posts, and we arrange that whenever a train enters on to any section, it automatically makes an electric connection between that section of the rubbed rail and the well-insulated conductor which supplies the power, and at the same time automatically cuts off the electric power from the section the train has just left, and in this way we confine the leakage of electricity to that section on which the train is at any particular time, and so reduce the leakage and waste of power on the longest electric railway to less than it is at present on the shortest line constructed on the Berlin plan.
But not only does a train on entering any section automatically turn on the electric power to that section, and cut it off from the one just left, but it accomplishes something more; it blocks absolutely the section just left. Let us take an example :â€”Suppose a train is passing from section A to section B, then not only is the power automatically turned on to section B and cut off from section A, but no following train entering on section A can receive power and move on as long as the train in front is on section B. It is not until the preceding train has passed into section C that the following train can proceed along section A. And, in addition, whenever a train is approaching too near a train in front, and in consequence finds itself deprived of driving power, it is automatically, by a special plan we have contrived automatically, powerfully braked.
Whenever, then, a trainâ€”it may be even a runaway engineâ€” enters on a blocked section, not only is all motive power withdrawn from it, but it is in addition automatically powerfully braked quite independent of the action of signalman, guard, or engine-driver, even if the latter two be present, which, bear in mind, is not at all necessary with our electric railway. No fog nor colour blindness, nor different codes of signals on different lines, nor mistakes arising from the exhausted, nervous condition of overworked signalmen can with our system produce a collision. The English system of blocking means merely giving an order to stop, but whether this is understood or intelligently carried out is only settled by the happening or non-happening of a subsequent collision. Our absolute automatic block acts as if the steam were automatically shut off, and the brake put on whenever the train is running into danger; nay, it does more than this, it acts as if the fires were put out, and all the coal taken away, since it is quite out of the power of the engine-driver, if there be one, to re-start the train until the one in front is at a safe distance ahead.
At present much household work is done by hand, simply because there are no easily-worked machines for doing it. The old knife-board has given way to the rotary knife-cleaner, but even that requires a certain amount of grinding to give the knives a polish, so that for large establishments a knife-cleaner boy is still necessary. The blacking of boots, the blacking of grates, the cleaning of doorsteps, &c, are all done in a most laborious way by hand. (I might almost say the operation seems not to be confined to hand, judging from the generally smutty appearance of Sarah Anne after the process.) Now, there can be no doubt that very shortly electricity will be supplied, as gas is now supplied, to houses for lighting purposes, and when this has been accomplished, the same wires that convey the electricity for lighting during the night will be employed in the day to convey the power to work electric-motors to turn rotary knife-cleaners, to turn a wheel for the blacking of boots, and a small motor carrying a brush like the one in my hand will simply be passed by the servant all over the grate for the purpose of giving it a good black polish. The black-lead brush will then be taken off, and replaced by the blacking brush for the boots, and later on in the day a rotary flannel will officiate for the door-steps.
The high price of land in towns necessitates gas works being in the suburbs, so in the future the electric works must be in the country, and probably farther away from the towns than even gas works are at the present time, because not only will great economy be so attainable, but the town will be freed from the smoke of the engines to drive the dynamo machines or producers of electric current, and by that time we shall have begun to realise that a smoky atmosphere is a poisonous atmosphere; further, if our dynamos are far away in the country advantage can also be taken of natural sources of water power.
The transmission, then, of power by electricity is not only a problem which must be solved, but is one which calls for immediate solution.
For the economic electric transport of power we must produce, as I have explained, a great difference of potentials by a dynamo at the place where the power is obtainableâ€”in the suburbs where, for example, is the steam engine or water wheelâ€”and employ some mechanism which can be worked by this great difference of potentials at the place where the power is to be utilisedâ€”that is, in the town. There is no difficulty in arranging a dynamo wound with fine wire, or a set of dynamos in series with one another, to produce any difference of potentials required; but there is a far greater difficulty in using this great difference of potentials at the town end of the line. If lamps and motors of the present construction are used they would have to be put in series, but in that case if the current is stopped passing through one it will be stopped passing through all. This difficulty can to a great extent be avoided by using "cut-outs," as I described to you in my last lecture. At the same time nobody would be perfectly satisfied that his supply of electric power should depend on the good working of all the electric apparatus in the same street, much less that it should depend on the good working of all the electric apparatus in the same town. We are content that our supply of gas or water should depend on the good working of the gas or water works, but we could not tolerate the possibility of Betsy Jane, in Moorgate-street, from some carelessness or other, being able to cut off our supply at the London Institution. That Jack Frost should stop our supply is bad enough, but Betsy Janeâ€” no!
What, then, are we to do? High difference of potential we must use, and we cannot work the lamps and motors in parallel unless they have a resistance of tens of thousands of ohms, in fact, are of a totally different description from the lamps and motors of the present day. The solution was first suggested by Sir William Thomson in 1881, and, I am happy to say, will very shortly be carried out in Paris by Professor Perry and myself, under the auspices of the French Electrical Storage Company. It is to use the small current and great difference of potentials to charge a very large number of accumulators, in series, in the town, and to discharge them in sets, as shown in the figure, each set supplying the energy for one street, or, possibly, for one district. Of course, the going and return wires between the dynamo and accumulators must be separately insulated, and put so far apart that there is no fear of a man or an animal accidentally touching both. If, in addition, it is feared that although this precaution is taken still somebody may touch a leading wire, say A, coming from somewhere near one end of the accumulators, while another person may accidently touch a leading wire, B, coming from somewhere near the other end of the accumulators, and so both receive a fatal shock, this may be also entirely avoided by electrically disconnecting the various sets of accumulators from one another, and from the main charging wires coming from the dynamo before they are connected respectively to the local leads in the streets for being discharged.
Suppose a thousand accumulators were thus employed, and a charging current of 33 amperes were used. To balance the electromotive force of the accumulators about 2,100 volts would be required. If the resistance of each cell were 0.005 of an ohm during charging, then 165 volts difference of potentials would be required to send a current of 33 amperes through this resistance, or a total difference of potentials of 2,265 volts would have to be maintained at the terminals of the accumulators. Hence about 100 horse-power would be put into them.
The next question that arises is, what size of conducting wire is it proper to use to convey a current of 33 amperes? If the conductor is thin it will certainly not cost much to erect; but, on the other hand, the resistance to the passage of the current will be great, and much of the power will be wasted in the heating of the wire. On the contrary, if the conductor is very thick, there will be practically no waste of power by the heating of the wire, but the capital sunk in erecting it will be excessive. It is clear, then, that there is some thickness which gives us the best results, and Sir William Thomson has worked out this problem for us, and has shown us that the thickness of the conductor proper to be used for any particular current does not depend at all on the length of the conductor, but depends first on the strength of current passing through the conductor; second, on the cost of copper per ton; and third, on the market value of one horse-power supplied for a year. Assuming that good conductivity copper costs Â£70 per ton, and that the market value of a horse-power is Â£10 per annum, the proper diameter to give to a conductor conveying a current of 33 amperes comes out to be 32-100ths of an inch, or a trifle over 3-10ths, on the assumption that the current passes for 12 hours out of every 24.
In order to send this 33 amperes through ten miles of going and ten miles of return copper wire, 32-100ths of an inch in diameter, as well as through the 1,000 accumulators, will necessitate the dynamo producing a difference of potentials of 2,654 volts. Under these circumstances calculation shows that about 17 horse-power would be lost in heating the line wires, about seven horse-power in charging the accumulators, and about a further 25 horse-power in the dynamo itself, which is in the country. 142 horse-power must, therefore, be given by the steam engine or water wheel to this dynamo.
We come to the conclusion, then, that if 142 horse power is given by the engine to the dynamo, 117 is given up by the dynamo to the wires; 100 is given up by the wires to the accumulators in the town, and 93 is stored up in the accumulators for future use, the total horse-power usefully stored up in the accumulators being in this particular case about 65 per cent, of that given to the dynamo by the engine.
The world thinks of a current of electricity as it thinks of a current of water. Now, there is this very essential difference between the supply of electricity to houses and the supply of gas or water to houses. When gas is supplied, you have only to deal with the quantity supplied; you are not going to use the pressure of the gas to do work, even if the gas is to be used in a gas engine. It is only the burning of the gas that you are interested in. You are really dealing, therefore, with quantity of gas. Similarly when water is supplied, nobody cares very much about the pressure so long as it is sufficiently high to reach the top story of his house. But if the pressure is 700lb. per square inch, as used by Sir William Armstrong, or 1,500lb. per square inch, as used by Mr. Tweddell, then the pressure becomes a very serious matter. Ordinary water is mainly used for drinking and washing purposes, and although this high pressure of water could also be used for drinking and washing, nobody but a millionaire would think of such extravagance; for it is not merely water, but water at a pressure of 1,500lb. per square inch that is supplied, and every cubic foot of water received per minute at that pressure by the consumer means 6 horse-power. In that case the pressure is all important, and for measurement you must take the quantity of water multiplied by the pressure. And although mere quantity of water may be important for washing purposes, we know of no purpose requiring mere quantity of electricity; it is needed as a source of energy to drive a motor, or to produce light, and the amount of energy, not the quantity of electricity, is what must be measured.
In any proper commercial recording meter for electricity a record must be kept, therefore, of two thingsâ€”the quantity of electricity and the pressure which it is supplied at. Now, the electric meter or "ergmeter," as we call it, designed by Prof. Perry and myself for this purpose, is hanging up here. It consists of a fairly good pendulum clock, possessing a seconds hand. The pendulum bob has been taken off, and a coil of wire of about 1,000 ohms resistance substituted in place of it. Fixed on the case of the clock, near the fine wire coil, there is a coil of thick wire through which the main current passes.
The current passing through the pendulum bob depends on the difference of electric pressure at the main where it enters the house and leaves the house, whereas the current passing through the thick wire coil is the total current works the lamps and motors. Now, the electric power being supplied to the house depends on the strength of one of these currents multiplied by strength of the other, and it can be proved mathematically as well as, of course, experimentally, that the total quantity of electric energy supplied to the house during any time, whether sometimes in the form of high pressure and small current, or sometimes in the form of small pressure and large current, is exactly proportional to the loss of the clock in that time. The number of minutes of slowness is the measure of electric energy supplied to the house, and is what should be charged for. An ordinary clock may doubtless lose a few minutes in a week, but we of course make the loss which we want to observe much greater than this. An ordinary clock wants winding up every week, but this of course is easily got over, and if experience in the future shows that the observations of the ergmeter by the electric inspector are only taken at distant periods that the clock would lose more than twelve hours between his visits, due to its measuring the electric energy supplied to the house in the meantime, then a hand will be added which takes, if we like, a day to make one complete revolution.
In the legislation which has recently taken place in connection with the commercial supply of electricity, a mistaken notion has grown up that the quantity of electricity is what should be recorded, and not electric energy. Now, not only is this bad in that it prevents an estimate being easily formed of the relative prices charged by the different companies for the supply of electricity, since the different companies use normally very different electric pressure, but even the most perfect system of governing dynamos, such as I described to you last time, or of laying the wires under the streets, such as has been suggested by Mr. Edison, will not enable the electric pressure at any house to he kept absolutely constant during the day, even if the electric pressure at the mains where they leave the dynamo is kept absolutely constant.
That is to say, with any system that has been hitherto suggested it is physically impossible, and, therefore, I need hardly say, cannot be made possible by legislation, to keep the pressure at a considerable distance from the producing station absolutely independent of the number of intermediate houses that are consuming electric power. In my opinion, then, we should not tolerate either the recording of, or the paying for the quantity of electricity supplied, but we must record and pay simply for electric power.
Two years ago the storage of electric energy in black boxes, and their power taken out of them by Sir Wm.Thomson, may have passed before the minds of the public as one of those mere seven days' wonders which in these latter times have become so common. But to the scientific man, who could foresee the possibilities connected with the electrical storage of power, these experiments of Sir Wm.Thomson were of pre-eminent importance.
The two latest employments of electricity stored in Faure-Sellon-Volckmar accumulators are in the boat "Electricity," which many may have seen running last Saturday at Kew, and a photograph of which I now project on the screen, and the electric tricycle of Professor Perry and myself. In the tricycle no work is done by the rider, but little black boxes carried on the baseboard contain the stored electric energy pretty much in the same way as a horse's body contains its breakfast of oats and hay, with the difference that with the accumulator it is the receptacle which has weight, so that neither in receiving its feed in the morning or discharging its power during the day does the accumulator gain or lose in its weight. By means of a tap the rider can turn on more or less electricity and go faster or slower. The faster he is going the less is the waste of the electricity, although, of course, the consumption of power is greater than when going slowlyâ€”that is to say, the faster the tricycle goes the more efficient is the whole arrangement. On the other hand, when the electric supply tap is turned off and the tricycle is at rest the waste in the accumulators is not large, and the tricycle stands for days ready for immediate use without any waste analogous with an unused horse "eating his head off."
But although the electric tricycle ceases using up its last supply of electricity when it stops, and requires no feeding while motionless, still it must be fed periodically if used regularly. But very shortly I expect to see the tricyclist dismounting at his innâ€”with the sign, perhaps, of the "Faraday "â€”having the certainty that in the morning he will find his accumulators fully charged up with the electric machine of the inn, also used for lighting and agricultural purposes. I feel also sure that when this is the case the charge in his bill for the electric feed will be one of the smallest items entered.
Let us now adjourn to the library to see our electrically-lighted and driven tricycle in actual operation, and which the size of this lecture hall, large though it be prevents my showing you here, and, that you may judge of the tricycle's power, I may mention that with it we have actually run a measured mile in 8 3/4 minutes, when the tricycle was carrying a man of average weight and the necessary supply of electric accumulators to propel it for about two hours.
What stored electricity can do the accumulators before you, kindly lent by the Electrical Power Storage Company, have shown. What the future of electrical locomotion may be who can say? The subject is yet young, very young. Improvements on what I have talked about to you tonight will no doubt be made. Perhaps Professor Perry and myself already see how some progress may be made. But at all events, I trust I have shown you that electric locomotion is already so far developed as to be a real commercial subject of discussion.
Tricycling By Electricity.â€”Professors Ayrton and Perry have brought out their electric tricycle. Its driving-wheel is forty-four inches, the electro-motor is placed beneath the seat, and the battery acts directly upon its cogged spur wheel. The battery is equal to two horse-power, and can be regulated with the utmost nicety.
And mixed with the mud was a liberal helping of manure, for city and country alike were dependent on the horse. The situation was grim enough in small towns, where the population might number a few hundred humans and a few dozen animals. It was far nastier in Fisher's Indianapolis, which despite bicycles and electric streetcars was home to a horse for every 14 people, or Kansas City, which had a horse for every 7.4. Boston's Beacon Hill, one observer recalled, had a "rich equine flavor."
Crossing a street could be an unsavory affair. In New York City, by one estimate, horses left behind 2.5 million pounds of manure and sixty thousand gallons of urine every day. That amounts to roughly four hundred thousand tons of manure a year â€” enough to float three Nimitz-class nuclear aircraft carriers and a half-dozen navy destroyers. Forget the smell and mess; imagine the flies.
Cyclists thus found their hobby not as pleasant as it could be, to say the least, and the League of American Wheelmen committed to doing something about it. A year after Fisher opened his store, the league launched a magazine, Good Roads, that became an influential mouthpiece for road improvement. Its articles were widely reprinted, which attracted members who didn't even own bikes; at the group's peak, Fisher and more than 102,000 others were on the rolls, and the Good Roads Movement was too big for politicians to ignore.
The New and the Old.
We have often gibed at the public for raising a howl of wholesale denunciation at any new utility as soon as a disaster occurred from its use, no matter if the ones it was displacing were ten times more dangerous, and demanding its instant suppression. There is not, and there never has been, any measure or perspective in these ebullitions: they are exactly like the Duchess's "Off with his head," in "Alice in Wonderland," or the action of the remarkable Cincinnati mob that burnt the court-house and a lot of pending criminal indictments by way of punishing lawyers and juries for letting off criminals. When locomotives were first introduced, one death on the rail outweighed a hundred from horses, and every railroad accident was the signal for a chorus from press and people demanding the suppression of railroads. The bicycle has hardly even yet emerged from the clond of public outlawry, although directly or indirectly it probably never caused a quarter of the accidents which base-ball and other sports have done. Kerosene was held a vile intruder in the place of camphene, though the latter is a worthy mate of nitroglycerine, and might have been compounded in Satan's own kitchen; and gas explosions made people sigh for the good old times of tallow candles, though these were incendiaries of a far more formidable kind. The explosions of kerosene and gasoline stoves have caused such determined attempts to put them under ban that one would think fires from overheated woodwork and other results of coal stoves were unknown; and natural gas simply bereaves some people of their senses. The deaths from electric-light wires are perhaps the latest subject of public determination to "have something done " about it; though it does not appear that any more people have been killed by them than by gas explosions. Modern Light and Heat, an organ of the business, is naturally disgusted by it, and "goes for" it in the following fashion: â€”
"We laugh at a savage because he attributes to a rifle which kills his comrades at a distance â€”and which he calls the thunder in the white man's hand
â€” mysterious and supernatural qualities; yet is he not as rational in so doing as an educated and civilized man who holds views relative to electricity as fantastic and outrageously absurd as those which constantly appear in the columns of the daily press? Until the public learns that danger is imminent wherever there is a manifestation of great force, whether it be accompanied with motion of large masses of matter or only the motion of molecules, electricity will not be treated fairly by the great mass of people.
"We venture to assert that there is nothing innately more unknowable about the force of electricity than about the force of gravity. We are familiar with one, not with the other. The time will come when every one will know not only that he must not let a brick drop fifty feet on to his head, but that it will be equally dangerous to permit an ampere to drop two thousand volts on to his head. There is but one way for the public to learn this, and that is by time. The present generation will never learn it,
â€” they are too old to learn; the generation now growing up will not learn it, for they are not being taught it. Perhaps our children's children may learn it: if they do, they will not fill their newspapers with feverish descriptions of the 'mysterious force' of electricity, but will very sensibly class it with a number of other things, such as steam locomotives and stationary steam engines, firearms, high explosives, and other agents of modern civilized life, which are tolerated by the public because they are necessary to our way of living.
"A few days ago, while walking on Washington Street, a cry was heard; the crowd parted, a horse dashed past dragging after him the wreck of a wagon, and then on the pavement at our feet lay a dead man, his clothes torn and muddy, and his face bruised and covered with blood. The crowd quickly gathered, and as the dead man was carried away, the people who lingered for a moment were loud in their expressions of sympathy for the poor unfortunate; but not one word did we hear of blame for the owner or driver of the horse, nor of protest against the hundreds of other horses which thronged the crowded thoroughfare, each one of which might in a moment become an element of danger and an instrument of death: and why? Because the horse is a familiar object. A brick falls from a roof and kills a man in the street, yet no one tirades against bricks: why? Because the ancients used them, and mankind has become accustomed to see falling bricks kill people. Now suppose a live wire falls into the street and a man is killed: instantly up goes the cry from every spectator, 'the deadly wires are threatening the lives of the public': and why? Because the electric-light wire, in the estimation of the general public, possesses baleful and almost supernatural powers for mischief."
The moral of all which is, â€” Whatever forces are impressed into the service of man, Insure in The Travelers!
Practical Chemistry and the Arts
BICYCLES AND TRICYCLES.
The application of mechanism set in motion by the feet or hands to four-wheeled carriages, was earlier than the idea of two-wheeled machines. In the London Magazine for August, 1760, there is an illustration and a description of "a chaise to go without horses, by a certain John Vevers." It appears to have been a true velocipede, a large, open carriage: and the footman sat behind, and worked certain levers; while the master, sitting in front, steered by a mechanism applied to the front pair of wheels.
In the early part of this century a strange machine, of French origin, was imported into England. At first it was called the "dandyhorse," afterwards the "hobby-horse." It appears to have become in a few months the rage of the fashionable world, then to have declined with equal rapidity. The decline was probably in part due to the storm of ridicule which the movement excited. The construction of the "dandy-horse " was very simple, â€” two wheels of equal size, one in front of the other, connected by a wooden bar. The front wheel could be twisted, by means of a suitable mechanism, to the right or left. The rider sat on the middle of the bar, his feet on the ground, and, by alternately pushing with his feet, propelled himself along. Nothing could well have looked more absurd than a gentleman exquisitely dressed in the fashion of the times, going along the muddy streets in this guise.
The velocipede took the place of the dandy or bobby horse. The history of the early machine is a history of isolated efforts made by ingenious mechanics, working under every kind of disadvantage. Machines were, however, produced, rough, complicated, and clumsy: a few showed distinctly germs of the modern improvements. The idea of two wheels, the one provided with pedals, took a practical form certainly as early as 1862; for in the exhibition of that year such a machine was shown: but it made no mark, nor was it until fourteen years later that any thing approaching the modern bicycle was adopted in England. In that year Mr.Charles Spencer introduced the two-wheeler, which has been called the "bone-shaker." The wheels are of nearly equal size. The machine is constructed of wood: it is heavy, and possesses a rigidity justifying its name.
From 1868 to the present time the record of the wheel has been one of progress. The substitution of iron and steel for wood, the invention of the spider-wheel, the application of india-rubber to the tire, and ball-bearings to the wheel, combined with almost perfect springs, have reduced friction and vibration to a minimum.
A few years ago a distinguished mathematician held that it was impossible for cycling to be a saving of labor; for, said he, you have to move your own body in addition to that of the machine. Experience has proved this view to be altogether erroneous, for distances can be accomplished by cyclists which are simply impossible to the mere pedestrian, and with less fatigue. The explanation, as given by an English writer, is simply this :â€”
When we stand or walk, the weight of our bodies presses on the ground, representing a force which in no way aids progression: it is lost. But on the wheel this force is utilized. The difference between walking and cycling is, then, as follows: Walking is wholly muscular exertion; cycling is one-third muscular force, two-thirds weight force, or gravity. The cyclist alternately puts his weight first on one pedal, and then on the other; and the chief part of the muscular force used is not used in directly rotating the pedals, but in this shifting of the weight of his body. A long walk tires the ankle-joints, the knees, and the hips, in part from the very weight they have to support: and this weight, so long as we walk, is continuous; but in cycling it is discontinuous. In cycling, the main stress is on the muscles in front of the thigh. In walking, the calves and the muscles moving the feet are among the first to get weary; but so little is this latter the case on the wheel, that a rider, after a long and sustained effort, often feels quite up to any reasonable amount of walking.
Tricycles are rapidly approaching in perfection the bicycle; and, though it is improbable that they will ever attain such high speed as the two-wheel, they have advantages which to a great extent compensate for a little slower movement. Tricycles are less dangerous; they are more comfortable for touring purposes, since a larger amount of personal luggage can be carried; and it is so much easier to stop when and where you choose, and enjoy the scenery. On the other hand, bicycles have not alone the convenience of swiftness, but of being easily stored: a bicycle can stand in a passage, in an office, or almost anywhere. Moreover, in case of injury to the rider or the machine, the bicycle and man may be readily conveyed by any other light carriage to his home or a railway-station.
Tricycles or bicycles are used at the present time by many rural postmen in different parts of the world, by clergymen, by medical men, and by policemen; and it has even been gravely proposed in England that a volunteer battalion of cyclists should be formed. This idea, at first sight whimsical, on close examination seems both feasible and practical. What quicker and more convenient method, indeed, is there of transporting in a few hours a thousand or two thousand men, armed with weapons of precision, to occupy a distant post, and hold it, for a few hours it may be, against a superior force, until the main body comes to their assistance?
Those who have marked the great development of cycling, as seen in the enormous manufacture, in the excellence, variety, and ingenuity of the machines, or in the periodical literature devoted entirety to the interests of cycling, or in the numerous clubs and associations, or, lastly, in the simultaneous rise of a hundred minor industries dependent on the greater, may well ask, Where will it end? Shall we yet have steam tricycles and electric bicycles? Already inventors are busy with devices of the kind. In any case, the wheel has its raison d'Ãªtre and its uses; and its great future may be confidently forecasted.
Crossing a street could be an unsavory affair. In New York City, by one estimate, horses left behind 2.5 million pounds of manure and sixty thousand gallons of urine every day
Ancient law snares man caught drink-driving riding electric bike
July 05, 2011
A man has been convicted after twice being arrested for drink-driving . . . on his electric bike.
Anthony Dancer, 23, was pulled over on his 15mph Fun Nine Electric scooter twice in a month after drinking sessions with friends.
But motorised bicycles, which do not need a licence, tax or insurance, are not covered under current drink-drive laws.
So Dancer was prosecuted under a rarely-used Victorian law dating back to 1872, originally drawn up to deal with carriages.
Oldham magistrates heard he was first arrested on February 11 after police spotted him pushing his motorised bicycle on Elm Road, Limeside.
He was found to be more than twice the drink-drive limit, with 83 micrograms of alcohol in 100 millilitres of breath. The legal limit is 35 micrograms.
Dancer, of Cherry Avenue, Alt, Oldham, was then stopped again on March 12 when police saw him travelling down a footpath on Ashton Road, Oldham.
He was again over twice the drink drive limit - this time there was 81 micrograms of alcohol in 100 millilitres of breath.
He was initially charged with being in charge of a vehicle while unfit through drink and drink driving, for both incidents.
But prosecutors had to alter the charges after learning his bike is not classed as a motor vehicle.
Instead he was charged with being drunk in charge of a carriage for the first offence â€“ as the pedals were not on the bike at the time â€“ and of being drunk in charge of a pedal cycle for the second offence.
Defending Dancer, who pleading guilty to the two offences, Richard Williamson, said: "When this bike was purchased he didnâ€™t think there was an offence of being drunk in charge of a carriage.
"Anthony has learnt his lesson and has stopped this sort of behaviour completely."
Magistrates fined him Â£200 and ordered him to pay Â£185 costs. The 1872 Licensing Act was originally brought in to crack down on anyone caught drunk in charge of a carriage, steam engine, a horse or a cow.
Most of the 1872 Licensing Act has been superseded but some of it remains in force.
The law still creates an offence of being drunk in public and of being drunk in charge of a carriage â€“ since reinterpreted to include bicycles. The offence has a maximum penalty of Â£200 or 51 weeks in prison.
sk8norcal wrote:would be sweet to electrify one of these,
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