constantly flowing water; the closets are ventilated, the soil-pipes are properly arranged and all traps are ventilated; in short, we found here a model job of plumbing.

Especially worthy of notice in this connection are the toilet sinks for pupils, with soap and towels, in the corridors, and the toiletrooms for teachers' use.

There are ten school-rooms, each 23x33ft., and of proper height. Each room is lighted by six windows, each containing eight lights of 18x22 glass, giving a glass surface equal to one-sixth the area of the floor, just the proportion that is considered most desirable. In two rooms the lighting is from the left alone, in eight from the left and rear of the pupils.

All the school-room windows are double, both outer and inner sashes sliding up and down. This is an important point in schoolhouse architecture in our climate. It will be seen that it is a very fortunate arrangement for this house.

The school-rooms are heated by radiators with double tubes; the inner tube being open at top and bottom to allow the air to pass through, the outer closed and containing the steam.* An opening through the outer wall of the building below the floor level, conveys air to the bottom of each radiator, in passing through which, it becomes heated and enters the school-room. There are three radiators in each room. The area of each air inlet is 36 square inches, or 108 square inches per room; and we found the air entering them at an average rate of 300 feet a minute. This is probably as great velocity as it is practicable to get, and is the maximum rate. at which it is considered advisable to allow air to enter an occupied room. A little calculation will show that, at this rate, 13,500 cubic feet of air an hour will enter each school-room through these openings. As this is only one-fourth or one-fifth the needed amount, it is not surprising that the teachers had found practically-what our measurements demonstrated scientifically-that it was necessary to keep the windows constantly open. By dropping the inner ssh at the top and raising the outer at the bottom, this could be done without inconvenience in the mild weather that had prevailed.

Turning to the ventilating apparatus proper, we are able to commend it in the highest terms. At the bottom of each 100m are three ventilating registers each of about one square foot available area. From each of these a galvanized iron pipe leads to the attic

*See "Double Tube Radiators," page 14.

where the pipes gradually unite and finally all combine into a five foot pipe, containing a five foot fan which drives the air into a ventilating tower above the roof. The fan is run by a water-motor. It was making 252 revolutions a minute and drawing the air through the ventilating registers at the rate of 200 feet a minute. was, however, easily run at a speed which gave a rate of 300 feet a minute through the registers. At the latter rate it affords very good ventilation; but at the former it is very deficient, as shown by the analysis made of the air in a primary room, which showed ten parts of carbon dioxide per 10,000. By closing the windows and doors of any room, leaving a chance for the air to enter only through the radiators, the rapidity of its exit was much reduced.

We conclude, that if the fan be run constantly during school hours at such a rate as shall maintain a flow through the ventilating registers of 300 feet a minute, the rooms will be very well ventilated -that with the present arrangement of inlets, it will be necessary to take a part of the air supply through the windows-that to make the system perfect, the ventilating apparatus should be complemented by some form of heating apparatus that would supply to each room, 50,000 to 60,000 cubic feet per hour of warmed air whenever heat is needed—not hot or partly hot and partly cold.

In warm weather, the fan run by a water-motor has a great advantage over the systems of ventilation dependent upon heated flues or a motor run by steam, because it can be kept running when heat is not needed, and will insure a proper change of air at the time when, from the slight difference between the external and internal temperature, natural ventilation is least efficient. Therefore the fan should be run when school is in session, all the year round and not simply when artificial warmth is necessary.

While in Lewiston we visited, by request of the committee, the other principal school-houses in the city.

The Bates street house is in an equally bad condition as when reported on two years ago,-it is inefficiently warmed by furnaces, has no proper ventilation, and the water-closets in the basement are abominable. It should be heated by indirect steam radiators, sufficient to furnish an air supply, supplemented by direct radiation for additional heat if needed. At the same time, some steam pipe

should be put into the ventilating flues to cause an upward draft, and new flues should be added. About the same can be said of the Grammar school-house, except that it is already heated by direct steam, it should be supplied with sufficient indirect radiation and ventilation. Both of these buildings should have new water-closets or school-sinks at once, and all their plumbing should be thoroughly overhauled. They are in a very unsafe condition at present.

The Main street school-house is in excellent condition and a credit to the city; is nearly new and is in many respects a model building; but it suffers from the same entire lack of air supply and ventilation-a lack with hich the High school-house is also afflicted. We hope the work begun this year will be continued until Lewiston can point with pride to all her school-houses.

NORTH GRAMMAR SCHOOL-WATERVILLE.

Dr. Webster of the Board, visited Waterville on February 11, 1890, and inspected the North Grammar school building-a new school-house erected some two years ago—and reports as follows:

This is a two-story brick school-house containing eight rooms, four on each floor, with large cloak-rooms adjoining, and spacious halls. It would well serve as a model for school buildings of this size.

Each school-room is 28x35 feet, twelve feet high. The windows are 36x76 inches glass surface. Two rooms have five windows on the left, the others four on the left and two in the rear. The glass surface is below the standard; though on the day of my visit, the lighting was satisfactory. Each room has a door opening into the hall and one into the cloak-room, both with transoms over them; and from each cloak-room there is also a door to the hall.

In the basement are short-hopper water-closets with a very fair flush, worked by the seat-not the best of closets, but kept in good condition by great care. On the boys side are slate-slab urinals with constantly running water. An abundant supply of umbrella racks is found in the dry, light and well cemented basement.

The heating is by steam with indirect radiation for air-supply, supplemented by direct for additional heating when needed. The indirect radiator boxes, air-supply pipes and hot-air flues are of galvanized iron, separate for each register.

The inner corner of each school-room is cut off, and the hot-air and ventilating flues run in the space thus formed. The warmed

air enters near the top of the room, through a register 12x18 inches. The ventilating register of the same size is near the floor. In the cloak-rooms, on the contrary, the hot-air register is in the floor, the ventilating register at the top of the room.

From each ventilating register a galvanized iron pipe leads directly to the attic where all enter a wooden box, six and one-half feet square and about the same height, situated under, and opening into the cupola which rises from the center of the roof. This box has three runs of one and one-half inch steam pipe around it on the inside, to create a current in the ventilating pipes.

room.

Careful measurements were made of the air-flow in four of the rooms, two on each floor; and it was found pretty uniform. The average in-flow of warmed air was 520 ft. a minute, which would give some 45,000 cubic feet of air an hour to each schoolThe rates as measured at the outlets were considerably less; but as no more air can enter a room than goes out, and vice versa, the larger number represents the amount of air actually supplied. If the doors between school-room and cloak-room are kept open, considerably more air-perhaps nearly twice as much-is available; for each cloak-room has the same air supply as a school-room.

For want of time, the air could be tested in but two rooms, and that just before noon. In one, with all doors, windows and transoms closed, the CO, rate was 9.5; in the other, which had the door into cloak-room open, 8.3 per 10,000. The temperature was very uniform, ranging from 70° to 74° in the center of the room. There are, on an average, about 40 pupils in a room.

The results here attained are so far superior to those found, as a rule. in our best school-houses, that we feel like bestowing only praise; and while, in future building, we should recommend an increased area of air-inlets and outlets in the school-rooms, we consider the conditions here highly satisfactory.

NEW MILLS SCHOOL-GARDINER.

On the 12th of the same month, Dr. Webster also visited Gardiner, and reports as follows:

The new school-house erected the past year at New Mills, Gardiner having been reported to be a model in respect to heating and ventilation, it was thought best to ascertain, by inspection, the truth of these reports. It is a two-story wooden school-house, of quite a pretentious outside appearance.

The halls are spacious, stairs wide with

short runs, two cloak-rooms to each school-room open from the hall, and entrance to the school-rooms is only to be gained through these, this part of the building is admirably arranged.

On entering a school-room, however, disappointment awaits one. The rooms are some 32 ft. wide, 30 ft. deep, and 12 ft. high, being much too wide for their depth. The lighting is from three sides, by 16 windows, 12 lights, 9x18 inches, six on each side and 4 in the rear. The heating is by direct steam, 4 runs of circulation pipe along the three outer walls. There are no air-inlets, and no attempt

at an air supply. There are ventilating registers behind the teacher's desk, opening into flues in the chimney that carries the smokeflue from the boiler. The lower registers are 11x15 inches. There are upper registers, for hot weather, now properly kept closed.

The rate of outflow was through register on first floor, 145 feet, on second floor, 230 feet a minute, carrying in the former case about 8,700 and in the latter 13,800 cubic feet of air an hour. The doors have to be kept open to supply fresh air. The air was tested in the lower room just after recess and found to contain 8.3 CO, per 10,000. With the doors closed it must soon become very foul, as is said to be the case.

It would be very easy to furnish an air-supply for these rooms by putting two indirect radiators into the cellar with about a sixteen inch supply and hot-air pipe to each, one of the latter opening by a large register into each school-room at some convenient place. Then if the ventilating flues be not efficient they can be heated by coils of steam-pipe. It is unfortunate that the windows on the pupils' right were not omitted a part of them being added to those on the left and in the rear. With the changes indicated, this would be-what it is not now-a healthful school-house.

We are glad to know that the architect was not responsible for these faults. His plans provided for just the things that we suggest, but they were well-nigh spoiled by the ill-advised changes made by the building committee.

CIRCULARS.

The following new circulars were published within the year. Circular No. 53 was written at the request of the school officers of several towns. The advance of our knowledge regarding the causes and possibilities of preventing that most destructive of all diseases,