Scientific American Supplement, No. 611, September 17, 1887 | Page 7

1 horse power on the track. There are to-day plenty of steam plants producing 1 horse power for work at from $30 to $50 per annum. Take the average, $40. With electricity then $65 would well represent the price of producing 1.54 horsepower.
With cable these figures would hold true, but more work is required. A greater loss is entailed. Since but 32 per cent. is recovered, the figure for 1 horse power on the track would be 2.86 horse power. At the above rates this would be $110 per horse power per year.
Our ratio here is: Electricity, 1; cables, 1.71; horses, 3.38.
This is by no means the whole of the story, for just here must we compute the depreciation and hence repairs due to time. Let us take the road figured on heretofore, and make three tables.
In the following I have under each system taken the estimated costs, allowed a fair per cent. for depreciation, summed up and obtained the ratios.
Any figure then like interest, etc., which would not affect ratios, I have omitted.
ELECTRICITY.
Conductors, 1 per cent. $160.00 Engine and dynamos, 5 per cent. 525.00 Cars, 10 per cent. 5,280.00 Roadway, 10 per cent. 2,007.00 ----------- Total. $7,972.00
HORSES.
Horses and appurtenances, 20 per cent. $7,780.00 Cars, 10 per cent. 2,880.00 Roadway, etc., 10 per cent. 3,500.00 ----------- Total. $11,740.00
CABLES.
Cable, 50 per cent. $7,500.00 Engine and boiler, etc., 5 per cent. 1,000.00 Cars, 10 per cent. 4,320.00 Roadway, 10 per cent. 3,500.00 ------------ Total. $16,320.00
These totals put in ratio are as follows: Electricity, 1; cable, 2.04; and horses, 1.47.
Placing all the ratios obtained in a table, we have the following:
Electricity. Horses. Cables. Depreciation. 1 1.47 2.04 Operating expenses. 1 3.38 1.71 Construction of tramway. 1 0.53 2.09 Motors, cars, etc. 1 1.63 1.21 Cars. 1 0.54 0.81 --- ---- ---- Totals. 5 7.55 7.86 Average. 1 1.51 1.57
Now this table must stand by itself for what it represents, and no more. It will be noted that I have not introduced the subject of men. This would unquestionably show favorably for both electricity and cable. Again, note, please, that this table does not represent your profits exactly as per ratios. I have to get them operated the same number of cars and under the same headway. Now with either electricity or cable a higher rate of speed can be maintained with but a very small proportionate increase of cost. This means quicker time, more trips, and greater receipts.
Evidently, as a financial investment, even if cost of maintenance and operating is greater, the cable is to be preferred to horses.
How is it with electricity? The ratios of expenses, etc., stand for themselves, the law of speed is far simpler than with cable, bringing even greater receipts, and again in practice the saving of coal in proportion to work done on track day or night is immensely more economical than with the cable. This point will be touched upon later.
6th. Individual characteristics and advantages.
Under this head a few of the salient features of each system will be mentioned. As the possibilities and limitations of the horse railroad system are, however, so well known, it is needless to go over them. I therefore will confine myself to the electric and cable systems.
With electricity single track lines, crooked streets, all descriptions of turnouts, crossings, branches, etc., are as easy to construct and operate as with horses. With the cable system they are either impossible or enormously expensive.
With electricity the line is not a unit, so that the complete stoppage of the whole line is absolutely impossible. With cable it is a unit and it is possible.
With electricity the life of the conductor is infinite; with cable, two years.
With electricity, and the improvements now being made in traction wheels, etc., the heaviest grades are as easily surmounted as with the cable; although it is true that for grades exceptional in character, such as 20 per cent. grades or over, I should be willing to give the contract to cable.
With electricity any speed can be attained by the individual cars. They are absolutely independent. Lost time can be made up, etc. With cable the cars are dependent upon speed of cable. Lost time cannot be made up except on down grades.
With electricity work done by engine is synchronous with work done on the track at any time of the day or night, with the loss of 35 per cent. due to the conversions in each case. In other words, for every horse power of useful work done on track the engine does 1.54 horse power. This ratio is constant. It makes no difference whether 1 or 100 horse power of work is necessary on the track, the engine has but to do 35 per cent. in excess.
With cable, if 1 horse power of work is all that is required