A more striking illustration of the advantages to the electric light company in the subdivision of power into the smallest possible units it would be hard to find. There is a difference in efficiency of from 15 to 20 per cent. in these two sizes of motors, but this difference is fully lost to the large motor in driving the shafting, and the small motor still has the advantage of being out of circuit entirely when the machine it is driving is stopped. There is scarcely a manufacturing industry which does not possess its busy and dull seasons. This means that in no industry will over 75 per cent. of the machines or machinery employed be in average operation. The entire shafting in the shops must be kept in operation the entire year, often for less than 50 per cent. of the machinery. Subdivide these same shops into as many small units as possible, and the current necessary to operate the shafting for this idle machinery will be saved, besides the saving from frequent stops while the machinery is in active use.

To return again to the list, the next two applications, picture frame manufacturers and moulding manufacturers, are very similar. Their busy seasons, as a rule, are in the spring and fall, and also follow closely any activity in house building. In the case of the larger manufacturers in this line, a maximum average of 75 per cent. will possibly be reached, but probably never exceeded. In the case, however, of the picture dealer who has a small shop in which he makes picture frames and mouldings to order the actual service of the motor will fall as low as 25 per cent. or 30 per cent. of its contract hours, one case in our experience the actual service having reached this low average. A fair general average in this class of works would be about 60 per cent.

The next application, nickel and silver platers and buffers, are good contract customers as a rule; one case in our experience showing but an average use of 20 per cent. of the contract horse power hours. This, however, is probably an exceptional case, and, as near as we can estimate on this class of work, the actual motor service will not exceed in any case 60 per cent. of the contract hours; a fair average being probably 45 or 50 per cent.

The next two applications, printing presses on news and job work, are probably met with more frequently than any other. On exclusively news work, the instances where the motor is in service more than 3 or 4 hours is rare. It is, however, usual in news offices to find two or more job presses. If the newspaper printed happens to be a morning paper, the hours of news work are usually between 12 midnight and 4 o'clock in the morning, the job work being done through the day. I have in mind a case of this description. In the shop is one cylinder press and three job presses connected to a 2 H. P. motor. This motor is on an incandescent circuit of 110 volts. To develop its rated power at 110 volts would require about 16 amperes in the motor. An ampere motor in series with the motor while running off the morning paper with only the cylinder press in operation stood at 12 amperes. For 3 hours this load was practically constant, when it was thrown off entirely. This gave on the night service but 30 per cent. of the contract hours. This motor required 5 amperes to drive the shafting, and but 8 amperes or one H. P. to drive the three job presses with the cylinder press off.

Here then is but a 50 per cent. use if the presses be used constantly; there are, however, many days when they are comparatively idle, 30 to 40 per cent., therefore, is a very safe estimate of the maximum use of this motor on the day circuit, or, had the motor been a 1 H. P., which would have been sufficient to drive the job presses, the use would be 60 to 80 per cent. of the contract hours, probably not above 60 per cent. All printing offices will probably come within this range, unless the motor be larger than is necessary to do the work.

Machine shops doing principally lathe work as a matter of course use a larger percentage of their contracted power than shops doing lathe and bench work with the same hands. In no case will the service of the motor exceed 65 or 70 per cent. of its contract use, for machine shops, like sewing machine shops, will never average over 75 per cent. of the shop capacity for operators the year round. The average, especially in the case of a shop doing much bench work, will fall as low as 40 per cent.

The driving of laundry machinery, which is our next application, usually proves a profitable contract, according to reports. This fact arises from the intermittent use of the machinery. The heaviest service on motor will probably be found during the early part of each week, with a general falling off in work during the summer months, while the patrons of the laundry are away at the sea-shore or in the mountains. In this application, therefore, a 75 per cent. service would probably be an exception, with, probably, many instances where the service would fall below 50 per cent.

The next application, model and pattern makers, are small users of power, as their occupation requires a large proportion of hand work. 50 per cent. service in the motor will be found a fair average maximum use, with instances as low as 20 or 25 per cent.

The next application, direct power or belt elevators, is another application frequently met. The average service in the motor is also much smaller than in any other elevator application. Let us suppose a case of the familiar grip connected to the ordinary hand hoist, with a lifting capacity of 2,000 pounds. In this case the motor is in use only going up, and the usual brake is used in coming down. Connected to this elevator, in the loft of the building, we have a 5 H. P. motor wired to a cut-out on the ground floor. We will call the lift 45 feet and the time consumed per trip 1 minute. We will allow 60 full trips of the elevator at full load, at 2,000 lb. per trip, each day. This would approximate 10 car loads of merchandise handled by the elevator, which is certainly above the average. This motor, we will say, is on a ten hour day circuit. Its possible horse power hours, therefore, would be 5 H. P. for 10 hours, or 50 H. P. hours per day. 60 trips of 1 minute each gives us exactly 1 hour's service of the full 5 H. P. or 5 H. P. hours.

To drive the shafting only while the elevator is coming down or idle would require about 150 volts or 1½ H. P., and if this was in constant operation the balance of the day, 9 hours, its total use on shafting would be 13½ H. P. hours, which, added to the 5 H. P. hours, gives us a grand total of 18½ H. P. hours, or 37 per cent. of the contract hours. If, however, the user of the motor avails himself of the cut-out box, and cuts the current out when the motor is not in use, the average use would drop to 20 or 25 per cent., instead of 37 per cent. In the case of a direct power passenger elevator, the use might possibly run up to 60 per cent., but this would be exceptional.

Coffee mills will average from 40 to 60 per cent. of their contract hours, manufacturing jewelers about the same, while retail jewelers will run as low as 25 per cent. Ice cream freezers will not average over 25 per cent., but as the contract season in this case is usually short, they should be rated at least a 50 per cent. basis, except possibly in cases where the customer pays the cost of installation and wiring, which is usual in these cases.

A dentist is one of the smallest of power users, so small, in fact, that if every one in a city were connected with a circuit, the load from this cause would never be felt. We will, however, put them down at from 10 to 20 per cent.

The optician uses a motor to turn his grind stones, and its use in this case will average from 20 to 30 per cent.

The last application on the list - church organs - uses only from 10 to 20 per cent. of the contract service.

These are, of course, but few of the very many applications of the electric motor, and if, as I trust, the possible subsequent discussion of this general plan may establish a basis for rating motor applications, not only will the objects of this paper be obtained, but a question of considerable annoyance now existing between the motor man and the electric light or power company will be solved.

In conclusion, Mr. Chairman, I beg to suggest that the supply and rates of charge for electric power have become of sufficient importance to this association to be represented by a permanent committee, whose duty it should be to obtain from the different members of the association, as far as possible, their experience in the supply of power in such manner and form as shall be deemed by the committee best suited to the wants of this association.

[1] Read before the electric light convention, New York, August, 1888.