Sept. 27, 1888] 



AWTL'kJi 



535 



you to appreciate the vast economical importance of using very 

 large electric pressures, and to grasp that, by substituting 2000 

 volts for 50 volts, when transmitting a certain amount of electric 

 power, the current can be reduced to the one-fortieth part, and 

 the waste of power, when transmitted along a given length of a 

 given wire to the one-fortieth of the one-fortieth — that is, to the 

 one sixteenth-hundredth part — your imagination will have been 

 kindled as well as amused. 



With a loss on the road of only 11 per cent., M. Deprez has, 

 by using 6ooo volts, transmitted 52 horse-power over a distance 

 of about 37 miles through a copper Wire only one-fifth of an 

 inch in diameter. A piece of the actual conductor he employed 

 I hold in my hand : the copper wire is coated with an insulated 

 material, and then with a leaden tubing, so that the outside may 

 be touched with perfect impunity, in spite of the high potential 

 difference employed. M. Deprez's dynamo and motor were not 

 nearly as efficient as he could make them now, so that his ter- 

 minal losses were unnecessarily great, and the efficiency of the 

 whole arrangement, wonderful as it was, was not so startling as 

 it would otherwise have been. I have told you that the loss in 

 dynamo and motor has actually been reduced to only 12A per 

 cent. ; so that, if a dynamo and motor of this efficiency had 

 been used by M. Deprez, the total loss in the whole transmission 

 over 37 miles would have been under 25 per cent. Indeed, by 

 using only 1250 volts, Mr. Brown has succeeded in transmitting 

 50 horse-power supplied by falling water at Kriegstetten to 

 Solothun, in Switzerland, five miles away, with an entire loss 

 in the dynamo, motor, and the five miles of going and returning 

 wire of only 25 per cent. ; so that three-quarters of the total 

 power supplied by the water at Kriegstetten was actually 

 delivered to machinery at Solothun, five miles away. 



In less than twenty years, then, from Gramme's practical 

 realization of Pacinotti's invention, we have power transmitted 

 over considerable distances by electricity with only a total loss of 

 25 per cent,, whereas the combined loss in an air-pump and air- 

 motor or in a water-pump and water-motor is 40 per cent," irre- 

 spective of the additional loss by friction or leakage that occurs 

 en route. We cannot help feeling that we are rapidly arriving 

 at a new era, and that it will not merely be for the inauguration 

 of the quick transmission of our bodies by steam, or the quick 

 transmission of our thought by telegraph, but for the economical 

 transmission of power by electricity, that the Victorian age will be 

 remembered. 



I showed you a little while ago an electric fire. Was that a 

 mere toy, or had it any commercial importance ? To burn coal, 

 to work dynamos, and to use the electric current to light your 

 houses and your streets is clean and commercial ; to use the 

 current to warm your rooms clean but wasteful, on account of 

 the inefficiency of the steam-engine. But when the dynamos are 

 turned by water power which would otherwise be wasted, the 

 electric current may be economically used, not merely to give 

 light, but also to give heat. And when the electric transmission 

 pf power becomes still more perfect than at present, even to burn 

 coal at the pit's mouth where it is worth a shilling a ton may, in 

 spite of the efficiency of the steam-engine being only one-tenth, 

 be the most economical way of warming distant towns where 

 coal would cost 20s. a ton. Think what that would mean ! 

 — no smoke, no dust, a reform effected commercially which 

 the laws of the land on smoke prevention are powerless to bring 

 about, a reform effected without the intervention of the State, 

 and therefore dear to the hearts of Englishmen. 



I am aware that this idea of burning coal at the pit's mouth 

 and electrically transmitting its power has quite recently been 

 stated to be commercially impracticable. But ; is that quite so 

 certain? — for in 1878 it was stated that, although telephones might 

 do very well for America, they certainly would never be intro- 

 duced into Great Britain, as we had plenty of boys who were 

 willing to act as messengers for a few shillings a week. The 

 phonograph was also declared to be worked by a ventriloquist, 

 and electric lighting on a large scale was proved to be too 

 expensive a luxury to be ever carried out. Putting a Conserva- 

 tive drag on the wheels is a very good precaution to take when 

 going down hill, but it is out of place in the up-hill work of 

 progress. 



To-day the electric current is used for countless purposes. Not 

 only is it used to weld, but by putting the electric arc inside a 

 closed crucible, smelting can be effected with a rapidity and 

 ease quite unobtainable with the ordinary method of putting the 

 fire outside the crucible. If one had pointed out a few years 

 ago that it was as depressing scientifically to put a fire outside a 

 crucible when you wanted to warm the inside, as Joey Ladle, the 



cellarman, found it depressing mentally "to take in the wine 

 through the pores of the skin, instead of by the conwivial channel 

 of the throttle," who would have believed that in 1S88, a 500 

 horse-power dynamo would be actually employed to produce an 

 electric arc inside a closed crucible in the manufacture of 

 aluminium bronze. 



But, of all the many commercial uses to which the electric 

 current may be put, probably, after the electric light, electric 

 traction has most public interest. The English are a commercial 

 people, but they are also a humane people ; and when, as in 

 this case, their pockets and their feelings are alike touched, 

 surely they will be Radicals in welcoming electric traction, what- 

 ever may be their political sentiments on other burning topics of 

 the day. It is not a nice thing to feel that you are helping to- 

 reduce the life of a pair of poor tramway horses to three or four 

 years : it would be a very nice thing to be carried in a tramcar 

 for even a less fare than at present. Now, while it costs 6d. or 

 jd. to run a car one mile with horses, it only costs t,<i. or 4*/. to 

 propel it electrically. 1 1 deed, from the very minute details that 

 have recently been published of the four months' expenses 

 of electrically propelling thirty cars at 7A miles an hour along 

 a 12-miles tramway line in Richmond, Virginia, it would 

 appear that the total cost — inclusive of coal, oil, water, engin- 

 eers, firemen, electricians, mechanicians, dynamo and motor 

 repairers, inspectors, lint men, cleaners, lighting, depreciation 

 on engine, boiler, cars, dynamos, and line-work — has been only 

 \\d. per car per mile. This is indeed a low price; let us 

 hope that it is true. The tramway is, no doubt, particularly 

 favourable for propelling cars on the parallel system (that is, the 

 system in which the current produced by the dynamo is the sum- 

 of the currents going through all the motors on the cars) without 

 a great waste of power being produced by a very large current 

 having to be sent a very long distance, becau>e the tramway 

 track is very curved, and the dynamo is placed at the centre of 

 the curve, with feeding-wires to convey the current from the 

 dynamo to all parts of the track. But even in the case of a 

 straight tramway line with a dynamo only at one end, it is- 

 quite possible to obtain the same high economy in working by 

 employing a large potential difference and by sending a small 

 current through all the trains in series, instead of running the 

 trains in parallel, as is done on the Portrush, Blackpool, 

 Brighton, and Bessbrook tramways. 



This series system of propelling electric trains was oddh 

 enough entirely ignored in all the discussions that have taken 

 place this year at the Institution of Civil Engineers, and at the 

 Institution of Mechanical Engineers, regarding the relative cost 

 of working tramways by horses, by a moving rope, and by 

 electricity ; and yet this series system is actually at work in- 

 America, as you will see from an instantaneous photograph 

 which I will now project on the screen, of a series electric tram- 

 way in Denver, Colorado ; and a series electric tramway 12 

 miles long, on which forty cars are to be run, is in course of 

 construction in Columbus, Ohio. The first track on which 

 electric trams were run in series was the experimental telpher 

 line, erected in Glynde in 1883 under the superintendence of 

 the late Prof. Fleeming Jenkin, Prof. Perry, and myself, for the 

 automatic electric transport of goods. A photograph of this 

 actual line is now projected on the screen. The large wall 

 diagram shows symbolically, in the crudest form, our plan of 

 series working : the current follows a zigzag path through the 

 contact pieces, and when a train enters any section the contact 

 piece is automatically removed, and the current now passes 

 through the motor on that train, instead of through the contact 

 piece. The Series Electrical'Traction Syndicate, whom we have 

 to thank for the model stries tramway on which the two cars are 

 now running, are now developing our idea, but it has received 

 its greater development in the States, where the Americans are 

 employing it, instead of spending time proving, a priori, that 

 the automatic contact arrangements could never work. Mental 

 inertia, like mechanical inertia, may be defined in two ways. 

 Inertia is the resistance to motion — that is- the English definition : 

 but inertia is also the resistance to stopping — that is the American 

 definition. 



In addition to the small waste of power, and consequent 

 diminished cos-t of constructing the conductors that lead the 

 current into and out of the passing trains, the series •-ys^m has 

 another very marked advantage. Some years ago we pointed 

 out that when an electric train was running down hill, or when it 

 was desired to stop the train, there was no necessity to apply a 

 brake and waste the energy of the moving train in friction, 

 because the electric motor could by turning a handle be con- 



