miles from the generating station, and the booster was arranged so that it could be readily connected to the high tension feeders. When it was necessary to replace broken insulators or make other repairs on the line the attendants were notified at the generating station and at the sub-stations, and at a pre-arranged signal, made by varying the voltage on the line, the alternators were thrown out and the booster thrown on in such a way that the power was only off from the trolley wire for a fraction of a minute. It was thus found quite practicable to make repairs on the line while the booster was in operation, and the system proved very satisfactory for supplying power at times of light load, while repairs were being made; the load on the booster frequently running as high as 500 amperes, at which time the voltage generated by the booster was about 500, which in addition to the 575 volts of the direct current system gave 1,075 volts at the generating end of the line; the voltage at the sub-station averaging about 450. While it would have been very expensive to run this booster for any great length of time, for the short time it was used the total cost was much less than the interest on the copper investment required to build a duplicate line. The fourth system mentioned, or three-wire system, is most applicable to double track lines, where one trolley is made positive and the other negative, there being about 1,000 volts potential difference between the two, the current flowing from the positive trolley wire through the car motors to the rail and from the rail through the car motors and the other track to the negative trolley. The track is usually cross-bonded and also connected to the conductor connecting the two generators which are operated in series in the station. This connection with the track forms the third wire and tends to equalize the voltage should there be more cars on one side of the system than on the other. This method of distribution is usually capable of saving from 20 to 40 per cent in copper, according to the character of the track return. If well balanced, it also greatly reduces the electrolytic action on buried conductors, such as water pipes, etc., and is most applicable where there are excessive track losses with fair opportunities for a balanced load. There are few roads in this country using the three-wire system of distribution, although it is used almost universally by lighting companies. This is probably due to the complications introduced in railway systems by the high voltage, usually about 1,000 volts. between the trolley wire and feeders on different sides of the system and the difficulty of balancing the load. The saving in copper, while not as great as in the three-wire lighting system, is still enough to warrant the extra complication, and under favorable conditions may prove very valuable. I am only familiar with one example of this system of distribu tion. In this case there is very heavy traffic over a double track line to a park, about six miles from the power station. It was found impossible to handle the increased traffic on the ordinary 500 volt system with the existing feedwire. By reinsulating the line and operating it on the three-wire system, the efficiency of the distributing system was very much improved and they were enabled to easily handle the increased traffic with the existing feedwire. The fifth system mentioned, or the alternating current system, is practically untried in this country. It seems peculiarly adapted to lines having long runs at uniform speed with few stops, such as lines connecting cities, rather than for ordinary street railway service. The alternating current motors at present in general use are of the polyphase type, and require at least three working conductors, which is a serious objection in many cases for railway work, as it necessitates the use of two trolley wires in addition to the track as conductors. The disadvantages of this system appear to be the necessity for at least two trolley wires and the probable difficulty in building alternating current motors suitable for railway work which will have a good power factor. The main advantage of the alternating current system is the possibility of feeding lines with stationary transformers which need no supervision, but which can be considered simply as a part of the feeder, thereby multiplying many times the length of line which can economically be supplied with power from one station. The alternating current motor also has the advantage of running at fairly constant speed independent of the load. It will not race going down hill if the power is left on, but will return power to the line, nor will it slow down much in going up hill. There are four or five railway companies using this system, and judging from the reports that appear from time to time in the railway journals it is giving very satisfactory results. The sixth system referred to, or storage battery system, is decidedly more expensive than the usual methods of electrical distribution, owing to the great first cost and the short life of the batteries. Lead is the only cheap metal capable of resisting the attacks of sulphuric acid, and modern batteries consist largely of lead, which is very undesirable from a mechanical point of view and is very heavy, so that unless the present type of storage battery is substantially improved, this system is only likely to be used where other systems are not practicable owing to peculiar local conditions or restrictions. The storage battery, however, has a large field in connection with the other systems of electrical distribution for street railways, and under favorable conditions may considerably increase the station capacity and reduce the fuel consumption; and when used on the line may greatly improve the regulation and increase the copper efficiency. From this brief outline of the various systems it will be seen that each has its peculiar advantages and that no one is suitable under all conditions. It will generally be found that where the traffic is heavy and the distance short, the standard 500 volt system is most applicable. For suburban work, where the distances are greater and the traffic less congested, or where it is necessary to transmit the power for some distance, the polyphase alternating direct current system will usually be found more economical. In special cases, where for short periods of time an unusually large amount of power is required, the "booster" system will often prove very valuable, while for high-speed, long distance, interurban work the threephase alternating current system may be attractive. The cars on this system, however, would have the great disadvantage of not being able to run over the ordinary direct current street railway lines. There can be no general rule given that will determine the most advantageous system of distribution to use under the varying conditions to be met in street railway work. Each case must be considered as a separate problem and that method selected which will best meet the peculiar conditions involved. Respectfully submitted, C. F. BANCROFT. President Roach-Gentlemen, we have gathered here for the purpose of disseminating information. You have heard the paper just read. We would be pleased to hear from some of the gentlemen who are present in reference to the subject matter of this paper. I will call upon Mr. E. C. Foster, of Lynn, Mass., to open the discussion on this paper. REMARKS OF MR. E. C. FOSTER ON "COMPARISONS OF THE VARIOUS SYSTEMS OF ELECTRICAL DISTRIBUTION FOR STREET RAILWAYS." Mr. Foster-Mr. President and Gentlemen: I thank you for calling upon me, but as I am not an expert electrician, it seems to me that I am hardly competent to discuss the merits of the paper which has been read. I think that Mr. Bancroft has treated the subject in a very broad way. He is a very competent man and is employed by the same companies which employ me. We consider him one of the ablest electrical en gineers in the Eastern country. I do not care to undertake to discuss this subject. There are many others here far more competent to do it than I, and I should be pleased to hear from Colonel Heft. I thank you for calling upon me, Mr. President. President Roach-Is Colonel Heft in the room? If so, we would be pleased to hear from him. As Mr. Heft is not present, I will call upon Mr. E. G. Connette, of Syracuse, N. Y., to give us his views upon the subject. Mr. Connette-I thank you, Mr. President, but I think, like Mr. Foster, that the paper is of such a technical nature, and the ground has been so fully covered, there is nothing that can be said which would be interesting in addition to what the author has already stated. President Roach-I can fully appreciate what the gentlemen have said, after listening to the paper. It certainly seems to cover the ground quite fully. We would like to hear from Colonel Dyer, of Augusta, Ga. Mr. Dyer-Gentlemen of the Convention: I am not at all prepared to discuss a technical paper of this character. I think that the subject has been treated most exhaustively, and it is a valuable paper. This Association certainly owes a debt of thanks to the gentleman who wrote it. I am wholly unable, however, to go into the details of the paper and discuss the advantages of the different systems which have been referred to. Mr. Connette-Mr. President, I would suggest, if you will permit me, that we hear from Mr. Charles W. Wason, of Cleveland. REMARKS OF MR. CHARLES W. WASON ON "COMPARI- Mr. Wason-Mr. President and Gentlemen of the Convention: It seems to me that the author of this paper has treated the subject in such a manner as to make a discussion quite out of the question. The fact is the condition of each road, as it presents itself, determines in a great measure the character of the electrical equipment. If we had a road under consideration which we desired to equip, then a discussion would be pertinent as to which one of the several systems presented would, in the minds of the gentlemen present, be competent to bring out the best results. President Roach-Gentlemen, you have heard the paper? What is your pleasure as to its disposition? Mr. Connette, Syracuse-I move that the paper be received and the thanks of the convention tendered to the author. (Carried.) President Roach-The next regular order of business is the reading of the paper on "Painting, Repainting and Maintenance of Street Car Bodies," by Mr. F. T. C. Brydges, Superintendent of Car Shops, Chicago Union Traction Co., Chicago, Ill. PAINTING, REPAINTING AND MAINTENANCE OF STREET CAR BODIES. The Secretary read the paper: The American Street Railway Association Gentlemen: In giving my views as to the proper manner in which to paint, repaint and maintain street car bodies, I thoroughly realize that it is a subject of the greatest interest to street railway men; and as it is a part of my daily duty to supervise this class of work, the subject is of the greatest interest to me, and I will endeavor to give my views on the three topics separately. PAINTING. Our object in painting a street car is two-fold: maintenance and durability of structure, and appearance. It is needless for me to go into the question of the increased life and durability of a street car, when properly painted, repainted or revarnished, as often as necessity may require to keep it up and maintain it in good condition, as it is an admitted fact that painting, repainting or revarnishing, as necessity may require, adds to the life and durability of street cars. Our methods of painting new cars are simple and, we think, very efficient. We apply our first, or priming coat, on all wood work to be painted, then putty all nail holes and other imperfections, and |