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 ngineers Society of Western Pennsylvania. 
 
 This Society does not hold itself responsible for the opinions of its members. 
 
 Tuesday, February 21st, 1888. 
 
 Society met at 8 o’clock, p. M., President Dempster in the 
 chair. 
 
 By invitation, the National Electric Light Association, now 
 holding a convention in our city, joined with us in this evening’s 
 meeting. 
 
 One hundred members and visitors were present. 
 
 The minutes of the January 7th meeting were read and ap¬ 
 proved. 
 
 Messrs. Isaac Winn, H. White and E. D. Estrada were elected 
 members. 
 
 The subject of the paper for the evening was “ Electric Rail¬ 
 roads,” by Mr. R. McA. Lloyd, the engineer of the electric railroad 
 now in process of construction on the “ South Side” of our city. 
 The introduction to the subject was made by Prof. A. E. Frost, 
 Treasurer of the Society, who, in language plain, clear and 
 forcible, explained the technicalities and terms in such a way as 
 to make even a tyro understand their meaning and application. 
 He illustrated his definitions of terms, as a teacher to his class, 
 with as much.force and freedom as if he were in the schoolroom 
 and the audience his pupils, whilst they, in return, showed their 
 appreciation by close attention to what he said, and many of them 
 were delighted with the lesson learned. , , 
 
 The reading of the paper by Mr. R. McA. Lloyd followed, viz.: 
 

 &%\- 3 3 
 
 ft 
 
 PA 
 
 14 
 
 ENGINEERS SOCIETY OF WESTERN PENNSYLVANIA. 
 
 •• 
 
 ■ » 4 •• • • * • • . 
 
 A Few: N$7*^/W*33LiJbTRic Railways. 
 
 # # •••••• 
 
 • • 
 • • 
 
 • • • 
 
 An electric.siij.wfy ffiftfajfs SaliS Jo# three parts : 
 
 First. A generating jtatioVw'herh tfie electricity is made. 
 
 Second. A npi»t^jd£ jbar^tf rftpelled on a track by electric 
 , motors. 
 
 Third. A medium through which the current is transmitted; 
 which medium may be either metallic conductors—overhead, sur¬ 
 face or underground—or storage batteries. 
 
 The field covered by each one of these headings has unfolded 
 so many times in the last few years that whereas, three or four 
 years ago, you might have been told in a half hour or so all 
 there was to know about electric railroads, at the present time I 
 can only attempt to bring to your notice, in a desultory way, a few 
 of their most conspicuous features. 
 
 Well, the generating station is a good place to start from. We 
 are all familiar with the appearance of a dynamo, and Prof. Frost 
 has just told us the principle of its action, but without going into 
 technicalities I might say another word about the dynamo. 
 
 The magnets of a dynamo literally resist every stroke of the 
 engine, every pound of steam pressure behind it, and as no power 
 can ever be lost, energy expended in one way must turn up in 
 some other form. The resistance which the dynamo magnets offer to 
 the engine is converted into an electric current, and the output of 
 the dynamo will be exactly equal to the horse-power expended in 
 driving its armature, minus a small proportion used to excite the 
 field magnets and a smaller proportion lost in friction of bearings 
 and heat. 
 
 The ordinary efficiency of a dynamo is 85 or 90 per cent., being 
 far higher than that of a steam engine; the efficiency of the latter 
 rarely rising above 15 per cent.; that is to say, a dynamo loses 
 but 10 per cent, in the conversion of mechanical energy into elec¬ 
 trical energy, while a steam engine loses 85 per cent, in converting 
 the energy of heat into mechanical energy. 
 
 It is a little ahead of my story, but here let me say that motors, 
 or receivers as we call them in distinction from generators, or 
 dynamos have the same efficiency as the latter. Both are built on 
 
ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 15 
 
 the same general principles, and the sources of waste are the same 
 in each. 
 
 The generating consists of a steam plant, engine, boilers, etc., 
 and one or more dynamos, besides a safety cut-out to protect the 
 dynamos from lightning and overloading. 
 
 It is not necessary to enumerate the smaller apparatus, but it is 
 important to state that no power station is complete without a 
 smaller space set apart for a repair shop, where a lathe and a handy 
 man with a few tools can save money for the company. 
 
 There are two simple methods of distributing electric energy, 
 both of which can be used for electric railways. They are, either 
 by a constant current of varying intensity, or by a varying cur¬ 
 rent of constant intensity. The former is the one used for arc 
 lighting and the latter for incandescent, and is also the easier, 
 safer, and more commonly used for the transmission of power. 
 
 Most of us prefer the constant tension method, but there are 
 various opinions as to the best standard of tension, and for my part 
 I should say that a good deal depends on the requirements and cir¬ 
 cumstances. I recommend (not only as being the system of the 
 company which I represent, but from considerable experience and 
 vivid recollections of personal contact with the subtile fluid) a 
 tension as low as possible. In respect to pressure, electricity is 
 analogous to gas or any fluid. You might sit on the opening of 
 an eight inch low pressure gas main, and thereby stop the flow, 
 but a seat on a two and half inch high pressure pipe would be a 
 difficult one to maintain. 
 
 Any E. M. F. or tension above 300 volts is dangerous to human 
 life and becomes troublesome in the matter of leakage. Greater 
 care is necessary all around. I do believe, however, that high 
 tension currents are advisable on a road of considerable length, 
 say in cases where the wires extend more than five miles from the 
 power station. Whatever may be the constant of tension, the dyna¬ 
 mos can be built to regulate themselves accurately, and—what is 
 the great beauty of electric transmission of power—produce just as 
 much electricity as the moment demands at the motors on the 
 road. The dynamos respond with a promptness that is simply 
 wonderful to every pull of the motors. But now we must hurry 
 on to the motors. They are running independently of each other 
 
16 ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 
 
 on the road. One, two, or a hundred can all get their current 
 from the same conductors and run in different directions with the 
 same current; and, so long as the capacity of the generating 
 station is not exceeded, will have no influence over each other. 
 
 The best place for the motor is under the car and directly sup¬ 
 ported by the axles which it drives, though some builders with 
 good reason put it on the front platform, which requires a special 
 construction of car and trucks, and an unsymmetrical suspension of 
 the wheels to compensate for the weight of the motor in front. 
 For very heavy service it is often convenient to have the motor 
 in a separate car. If the motor is situated on a car platform 
 the motion of the armature is communicated to the car wheels by 
 sprocket chains or belts. 
 
 When the motor is placed under the centre of the car, tooth or 
 worm gearing is used to drive the car axles. It is quite common 
 to equip a street car with two motors, one on each car axle, so that 
 if one motor should be disabled its mate could bring the car home; 
 on the other hand, it is very rarely that a well cared for motor be¬ 
 comes so worthless in one trip that it can’t pull itself home; and 
 if such a case should occur, the next car that comes along can 
 push the disabled one ahead of it. Motors can be built for any 
 desired speed and for the development of any desired power. As 
 adapted to tramway service, they are generally arranged so that 
 the speed may be varied by the driver of the car. The weight of 
 motor with gearing and all other apparatus included in the elec¬ 
 trical equipment of a tramcar, capable of doing the work of a 
 first class team on any of the Pittsburgh railways, would be 1,500 
 pounds. 
 
 The nominal capacity of such a motor would be seven or eight 
 horse-power, with the ability to work up to fifteen horse-power 
 when necessary, as when starting a heavily loaded car on a seven 
 per cent, gradient. 
 
 It has been demonstrated by the use a of dynamometer between 
 the car and whiffletree, that a pair of horses often exerts this 
 enormous strain under like conditions. 
 
 The current is generally carried from the generators to the 
 motors by overhead conductors, that being the cheapest method, 
 though there is no reason why underground conductors in conduits 
 
ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 
 
 17 
 
 similar to those of cable railway?, He' irsed with equal satis¬ 
 
 faction. As for surface conductors’, Meaning a,third rail insulated 
 from the ground, they* arle, i hot; permissible hi any common 
 thoroughfare, and so will’mol ’denfaild our atteption this evening. 
 
 The overhead conductor may Jsupp-orf$f in -many ways, either 
 at the side of a street or in thVcferftre, and usually at a height of 
 20 feet. It consists of one or two hard drawn bare copper wires, 
 stretched more or less tight and suspended in such a way that 
 its supports do not obstruct the passage of a rolling trolley. The 
 trolley may consist of one, two, or more rolling sheaves, combined 
 with a view of traveling easily on the wires without falling off. 
 The car tows its trolley along by a flexible cable, which also 
 carries the current down to the motor. 
 
 The thickness of the overhead conductor is based upon the 
 amount of current which it is required to carry, and for the trans¬ 
 mission of the same amount of power depends on the electro¬ 
 motive force or tension. Just as a small pipe may transport as 
 much gas or water at a high pressure as a large pipe can at a low 
 pressure, so a small wire can carry as much power at a high ten¬ 
 sion as a large wire at a low tension. It is, therefore, evident that 
 the high tension presents a saving in first cost of copper wire. 
 The cost of the wire is, however, such a comparatively small item 
 in the equipment of an electric railway, that it is overbalanced by 
 the considerations of safety and insulation; and if we would have 
 a road which could be guaranteed free from danger in case of 
 accidental contact with the current, and at the same time not too 
 wasteful of copper, we must strike a medium which may be 
 worked out from two standpoints. We may either adopt a tension 
 which will be as high as possible without being dangerous, or as 
 low as possible without requiring an enormously large conductor. 
 
 In parallel systems of distribution which I have described, it 
 is only necessary to insulate one side of the circuit, just as in 
 water power it is only necessary to save the water in the dam. 
 After the water has gone through the wheel to the pool below, it 
 is useless so far as anv influence on the same wheel is concerned. 
 
 If one side of an electric circuit is insulated so as to dam it up, 
 as it were, we do not care what becomes of the current when it has 
 gone through the motors to the other side ; it is, therefore, quite 
 
18 ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 
 
 common to use the r$ils fen »the return to the dynamos—corre¬ 
 sponding to the pool below the mill-dam. 
 
 The current, then .goes fromv the Insulated conductor through 
 the motor, and by way of' the wheels to-the rails and back to the 
 
 J c < f c* 
 
 dynamos. When a'iwSce/is used for* the return instead of the rails 
 
 • • ‘ c « < < < 1 ' . (t ; < 
 
 it serves in the same capacity,'and the return current has no power 
 to lose by bad insulation. Where the rails are likely to be con¬ 
 tinually buried in dust, or other dirt, it is so difficult for the 
 wheels to maintain a metallic contact with them, that the return 
 by an overhead wire is preferable, and there must be either a sin¬ 
 gle trolley on each wire, or a double trolley bearing on the two 
 wires at once, with the wheels on one side insulated from the 
 wheels on the other side, and communicating with the car by a 
 double cable through which the intense current proceeds to the 
 motor and the spent current returns from it. 
 
 An electric railway using line conductors is a unit. The gener¬ 
 ating plant, the conductors and the motors are inseparable. In 
 order to keep the motors running, the conductors must be kept in 
 order, and the dynamos must generate continually; but where 
 storage batteries are used the case is different. I need not describe 
 to you a storage battery, beyond telling you that enough of it to 
 run a street car four hours under ordinary conditions, weighs at 
 least 2,600 pounds, and occupies the space under the seats on 
 both sides of the car. Every car possessed of a motor and stor¬ 
 age battery is independent, except when the battery gets short 
 circuited and the stored energy runs out, in which event it has to 
 be hauled home by animal power. 
 
 There is, doubtless, a large field of usefulness for storage bat¬ 
 teries, and the subject would be interesting to dwell on, but at the 
 present time they are too costly, and not far enough perfect for 
 every day wear and tear on a city street. I do not make this 
 statement from any personal prejudice, but as the opinion of a 
 great many people of wide experience in electric railways. My 
 own company is prepared to equip roads with storage batteries 
 when wanted, but we do not recommend them. 
 
 I may say also of storage batteries, that their use entails a 
 further loss of 20 per cent, in the transmission of power from 
 dynamos to motors, and, therefore, necessitates a power plant of 
 
ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 19 
 
 proportionally greater eapacity. The batteries, consisting of cells 
 containing lead plates and acidulated water, are charged at the 
 power station, or car shed, by the dynamo current, and fresh sets 
 slipped under the car seats 'about every four hours. When a 
 more lasting material has been found to take the place of lead in 
 storage batteries we shall look for better results in that quarter. 
 A car supplied with current by an overhead or underground 
 conductor has an unlimited source of power to draw from, but 
 one dependent upon storage batteries may, by a heavy pull, run 
 out of power and have to bear the mortification of a homeward 
 trip with a mule team. 
 
 Having briefly touched upon the three elements of an electric 
 railway—the generating station, the motors, and the medium of 
 transmission— I shall now glance at some of the minor features. 
 
 Electric brakes are a common and simple institution, and almost 
 anybody can devise a very practicable one; but the old hand brake 
 is after all the most reliable for street car service. There are, 
 however, several ways of controlling an electric car on down 
 grades without the use of brake shoes. On the motors of the St. 
 Clair road, on the South Side, we have provided an arrangement 
 of current switches, by which the heaviest load may be safely 
 and smoothly carried down a hill, the equal of which has never 
 before been attempted by any mechanical tractor. We take a 
 little current from our line wires—about 1J horse-power from the 
 dynamos to magnetize the motor, or, more accurately speaking, to 
 excite the field magnets ; then we allow the motor to act as a 
 generator, converting the force of gravity which pulls it down 
 hill into electricity. Perhaps I have not clearly explained that 
 generators and motors are practically the same in principle, so 
 that a generator may be used as a motor, or a motor as a generator. 
 
 Well, the same gearing by which the rotating armature of the 
 motor drives the car up hill, going down hill transmits the motion 
 of the car axles back to the armature, and as the armature revolves 
 about ten times as fast as the car wheels, it is not necessary to run 
 down hill very fast to obtain a high speed for the armature, and 
 as the current generated by the armature is proportional to its 
 speed of rotation in a constant magnetic field, and as the work of 
 driving the armature increases with this current, it stands to reason 
 
20 ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 
 
 that the faster the train runs the greater power resistance it will 
 offer to its own descent. 
 
 This amount of current or retarding power can also be in¬ 
 creased by diminishing the resistance of the armature circuit, for 
 which purpose we provide a variable resistance to be operated by 
 the driver with a small turning handle. 
 
 Cars may descend hills with ease using this device, but I do 
 not consider such methods necessary except on extraordinary 
 grades, and recommend the omission from an electric car of 
 everything that is not absolutely necessary, for complications of 
 wires need much careful watching. 
 
 Electric cars should be lit by electric lights, but as for electric 
 bells, electric heaters, electric indicators and fare boxes and other 
 electric fixings, they are nuisances which do well for advertising 
 without adding to the serviceability of a hard working road. 
 
 I have been asked a hundred times whether ice and snow inter¬ 
 fere with the operation of electric tramways. 
 
 Ice and snow interfere with electric tramways just as much as 
 with horse roads. Any track which a horse car can safely go 
 down on, is good enough for an electric car to go down or up on; 
 for if the wheels of the horse car can get enough hold to go 
 down on it without coasting, the wheels of the electric car will 
 take sufficient hold of the same track to climb up it. In 
 short, salt and sand keep an electric road running in winter as 
 well as they do a horse road, with the advantage that there are no 
 horses’ feet to be ruined by salt. 
 
 The advantages of electricity over horses are many. Speed, 
 perfect control, easy stopping and starting, and economy. I won’t 
 bother you with estimates, but from the experience of the roads 
 with which I have been connected, I can assure you that street 
 cars can be run by electricity for less than one-half the expense of 
 horses, and at the same time give the public better service, and in 
 consequence reap a greater reward. Besides this, the ground re¬ 
 quired by an electric railway plant is small to that of a horse 
 stable, to say nothing of the difference in the character of the 
 employee. Last, I may remind you that electricity never gets 
 the pink eye. 
 
 A more formidable rival of electricity is the cable. It is a 
 
ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 21 
 
 good thing, and claims, in common with the former, a great many 
 of the advantages which I have just enumerated, but in cost the 
 cable is away ahead of us. 
 
 Electric railways have so far been built too economically, but I 
 am very moderate in statement when I say that an electric tram¬ 
 way can be built in any street in your city for $25,000 per mile, 
 which will give as much satisfaction as the cable at $100,000, and 
 that the cost of operating will be less. 
 
 However, as I have neither been invited to run down cables 
 nor run up electricity, I shall not produce all the evidence which 
 would surely convince you that electricity is the ideal power for 
 street railway purposes, and that however ludicrous some of the 
 experimenting has been, it is to-day as reliable as the mule or 
 cable. Of course there are systems on the market which are no 
 credit to the mighty force itself, but there are several companies 
 that after years of discouraging work have brought their hopes to 
 commercial success. 
 
 After which Dr. Moses, of New York, said: 
 
 The question of electric motors is one that is now so full of 
 interest that I can be prompted to say something about them. I 
 may say something that may be novel, as I have had opportunity 
 of seeing quite recently abroad the development of electric 
 motors there, and of hearing some expressions of opinion as to 
 their probable future for use where other sources of power are 
 now employed. 
 
 I was recently in London, and visited a gentleman who is con¬ 
 nected with the Metropolitan Underground Railway. He had been 
 looking into the question of motors, as also other stockholders, 
 some of whom had come over to this country for the purpose of 
 studying the matter. The Duke of Sutherland, who is, perhaps, 
 the largest stockholder of the railroad, has given a great deal of 
 personal study, as well as have his engineers, and a contract has 
 been given out recently to Dr. Siemens (Siemens Brothers), of 
 London, for the purpose of putting in a considerable section of 
 electric railway in the Underground Railway of London. 
 
 I do not think I could, by any further expression of my own 
 opinion, give you a greater idea of what importance electrical 
 2 
 
22 ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 
 
 motors have assumed, than when I tell you that the Metropolitan 
 Underground Railway is one system and the only system of rapid 
 travel in London. There are many omnibus lines, there are 
 some horse car lines, but the only artery for rapid transportation 
 in London is the underground railway. 
 
 The disadvantages of steam have become so apparent there that 
 they have made up their minds to abandon it at the first oppor¬ 
 tunity, which will be the presentation to them of a successful 
 system of electrical transportation. 
 
 It is true the conditions there are all favorable. You have an 
 underground road protected from the weather, and no snow or ice 
 which are found so objectionable to horse cars. You have no rain 
 to fill up vour conduits; no conductors; you have no teams cross¬ 
 ing the road. Short circuit cars of course doubles them up. You 
 have no persons interfering with the line; no small boy down 
 there ; and altogether the conditions are very favorable. 
 
 Again, on the other hand, the most favorable recommendation 
 to the introduction is the fact that the atmosphere is absolutely 
 intolerable. The foggy condition of London is such that when a 
 puff of smoke gets down there it stays, and there is no way 
 of getting it out, and the result is a most intolerable condition of 
 affairs. I always preferred to go by cab to taking the under¬ 
 ground road. 
 
 Now they have investigated the system, and I was called upon 
 by Dr. Hopkinson to look into the question for them, and one of 
 the most important systems of electric distribution now in use in 
 America, verv successful!v, was under consideration bv them; 
 they are very willing to give them a trial. I was told by Dr. 
 Siemens himself, that he was perfectly willing to undertake and 
 introduce this American system in place of his own, provided 
 certain arrangements were made. 
 
 In regard to the introduction of electric motors in Paris, I will 
 say this, that there is now before the Municipal Council of Paris a 
 proposition on the part of some cable roads, in successful opera¬ 
 tion in New York and on certain English railways, to put a 
 complete line around Paris between the fortifications and between 
 the tramways, as they are called, but this question, owing to 
 legislative and governmental disturbance, has been cast aside for 
 
ENGINEERS’ SOCIETY OF WESTERN PENNSYLVANIA. 23 
 
 " < . 1 
 
 the time being. There is, however, under advisement, a system 
 of electrical transportation it is proposed to introduce in France, 
 which has some very interesting features connected with it. 
 
 This system has certain very great advantages. I mention 
 them to you as I believe they are novel. The cars are run on 
 high tension, the current in multiple arcs, and they are not in¬ 
 terfered with by the potential on the line, because feeders are sent 
 out at certain very short intervals for the purpose of supplying the 
 current, and in that way keep up the potential. It is necessary 
 that the potential should always be uniform, as you know, and 
 although, as has been said, quite a large number of motors can 
 be run on the same line, it is only under certain favorable condi¬ 
 tions, because they are like incandescent lamps, strong in multiple 
 arcs along a single line. 
 
 There is a fall of potential due to the resistance of the wire. 
 This fall is relatively great, and it has been found necessary to 
 send out feeders. Now it is very necessary that you should avoid 
 this fall of potential, hence the sending out of these feeders. One 
 trouble had to be looked to, however, and that was the small boy. 
 I was told by Mr. Payne, engineer of the Brooklyn bridge, that 
 at first it was impossible to keep the conduits clean, and that they 
 gathered up all sorts of rubbish that could possibly be imagined. 
 
 The genius of the inventor has, however, circumvented him, by 
 arranging that when receiving the current the car covers the vul¬ 
 nerable point. I do not know but that there will be found some 
 Achilles heel in it where the small boy will finally get in his 
 work, but as at present devised, it is only when the car covers a 
 certain length of rail that it is possible for the current to operate 
 in the motor. 
 
 With this, exception, the overhead arrangement is preferable as 
 being safer, though we have still seen the cats and kites of the 
 small boy suspended from the poles. 
 
 This is the arrangement proposed to be introduced in Paris. 
 The cable people are confident of their scheme, but so are the 
 electricians. 
 
 Society then adjourned for social intercourse with the visitors. 
 
 S. M. WlCKERSHAM, 
 
 Secretary. 
 

 
 ' 4 :.