operated by compound and triple pumps. The ground floor contains a number of handsome stores, brilliantly illuminated, while the rest of this floor is given up to public rooms and restaurant.

The approximate connected capacity of lighting is 750 kw. and the maximum load is 450 kw. from 6 to 8 p.m.

The ratio of maximum load to connected capacity is therefore about 60 per cent.

In this hotel the electric plant seldom uses over 300 h.p. during the day and 600 h.p. at night, whereas the boiler horse power developed frequently exceeds 1000.

The balance is made up of the steam supplied to elevator

pumps, half a dozen other steam pumps, laundry, kitchen and refrigerating plant.

During the cold weather the exhaust steam from all the apparatus does not suffice to heat the building, and additional boiler steam is needed.

It is not unusual in the building to burn 40 tons of fuel in a day, and 50 tons have been burned in extreme weather. This latter consumption indicates an average of 1000 h.p. for the whole 24 hours. During the cold season it is evident that the electricity is really a by-product of the heating, in so far as the fuel is concerned. A distributive test showed that the electric plant used about seven-eighteenths of the total steam supplied.

Curves 3, 4 and 5 show conditions in high-grade housekeeping apartment houses. The three curves represent different conditions.

Curve 3 is an apartment house in which electricity is supplied free with rent. The refrigerating plant and pumps are steamdriven. The building is twelve stories and basement, and the apartments are large, 34 in all which rent from $3,000 to $4,000 per year. The building has its own electric and refrigerating plant, electric elevators, but no storage battery.

The curve shows the steady load, and elevator fluctuations. are additional and reach as high as 30 kw. The connected capacity, excluding elevators, is 100 kw. The ratio of maximum load to connected capacity is 70 per cent.

Curve 4 is from an apartment house of the highest class, in which electricity is sold to the tenants at the standard central station rates, although made on the premises. The building covers a block 200 by 100 ft. (61 by 30 m.), 12 stories and basement, containing 48 apartments. The different character of this load curve is largely due to the operating of an electrically

driven 15-ton refrigerating machine. A large storage battery acts as auxiliary to the electric plant, and at one o'clock every morning the engines are stopped and the electricity is supplied from the battery.

Curve 5 is an apartment house, two elevators, with 72 apartments, which rent for about $280 to $300 per room per year. The building covers a block and has 8 stories and basement. The maximum load is 38 kw., exclusive of elevators, and the

connected capacity about 100 kw. The ratio of maximum load to connected capacity is about 40 per cent.

Curve 6 shows the electric load variations in an apartment house of the best grade. The apartments are of from five to