Page:Popular Science Monthly Volume 74.djvu/221

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installations already mentioned have announced that the electrical operation of the former steam service is being handled with the consumption of only 60 per cent, of the amount of coal, resulting in a saving of nearly $350,000 per year. Figures have been published showing that the Manhattan Railway under steam operation secured about 1.5 ton miles to a pound of coal; under electric operation this figure has increased to 3.85. These and other careful estimates indicate that in the general electrification of through railway lines a saving of 50 per cent, in coal consumption may be effected. It is to be noted, however, that the cost of fuel alone is only about 12 per cent, of the total cost of operation; therefore, a saving in this respect would be only 6 per cent, of the total operating expense. In the kindred items of firemen, roundhouse men and other expense peculiar to the steam locomotive a further saving of about 5 per cent, is possible. It is interesting in this connection to consider the effect of this fuel saving on the total coal supply of the country. The fuel consumption of all the locomotives in this country in 1905 was about 52,000,000 tons, which was about one eighth of the total coal production of that year. The total coal consumption, therefore, would be reduced by about 7 per cent, if all the railways in the country were electrified. This does not appear to be a very important reason why railways should electrify; but with trans-Atlantic liners burning 5,000 tons of coal per voyage and the end of the coal supply of the state of Ohio in sight within 25 years, any influence tending to check coal consumption must soon assume importance.

The repairs to steam locomotives amount to about 8 per cent, of the total operating expense. The repairs to an electric locomotive amount to far less. The greater simplicity of the electric locomotive has already been noted. There are now available plentiful data based on experience indicating that the above figure of 8 per cent, may be reduced to the neighborhood of 2 per cent. An additional saving in the maintenance of track and other less striking items offsets the repairs to track bonding and overhead construction and leaves an additional saving in favor of electric operation of about 3 per cent. The aggregate of the above economies in operating expense amounts to 20 per cent., which should be readily available by any of the large railway systems in the transformation to the electric method of operation.

Considering further the several pioneer installations of electric service, we find that they differ materially in their characteristics and there are several so-called systems at present available. The early development of the electric railway for operation in cities was entirely dependent on the use of the direct current motor as the only motor available. This motor had been developed in spite of the fact that the earliest electromagnetic generators were of the alternating current