[1] Pettenkofer and Voit: Ann. der Chem. u. Pharm. (1862-3), Supp. Bd. 2, p. 17.
[2] Atwater, Woods, and Benedict: Report of preliminary investigations on the metabolism of nitrogen and carbon in the human organism with a respiration calorimeter of special construction, U. S. Dept. of Agr., Office of Experiment Stations Bulletin 44. (1897.)
[3] W. O. Atwater and F. G. Benedict: A respiration calorimeter with appliances for the direct determination of oxygen. Carnegie Institution of Washington Publication No. 42. (1905.)
CALORIMETER LABORATORY.
The laboratory room is entered from the main hall by a double door. The room is 14.2 meters long by 10.1 meters wide, and is lighted on three sides by 7 windows. Since the room faces the north, the temperature conditions are much more satisfactory than could be obtained with any other exposure. In constructing the building the use of columns in this room was avoided, as they would interfere seriously with the construction of the calorimeters and accessory apparatus. Pending the completion of the five calorimeters designed for this room a temporary wooden floor was laid, thus furnishing the greatest freedom in placing piping and electric wiring beneath the floor. As fast as the calorimeters are completed, permanent flooring with suitably covered trenches for pipes is to be laid. The room is amply lighted during the day, the windows being very high, with glass transoms above. At night a large mercury-vapor lamp in the center of the room, supplemented by a number of well-placed incandescent electric lights, gives ample illumination.
GENERAL PLAN OF CALORIMETER LABORATORY.
The general plan of the laboratory and the distribution of the calorimeters and accessory apparatus are shown in fig. 1. The double doors lead from the main hall into the room. In general, it is planned to conduct all the chemical and physical observations as near the center of the laboratory as possible, hence space has been reserved for apparatus through the center of the room from south to north. The calorimeters are on either side. In this way there is the greatest economy of space and the most advantageous arrangement of apparatus.
At present two calorimeters are completed, one under construction, and two others are planned. The proposed calorimeters are to be placed in the spaces inclosed by dotted lines. Of the calorimeters that are completed, the so-called chair calorimeter, which was the first built, is in the middle of the west side of the room, and immediately to the north of it is the bed calorimeter, already tested and in actual use. On the east side of the room it is intended to place large calorimeters, one for continuous experiments extending over several days and the other large enough to take in several individuals at once and to have installed apparatus and working machinery requiring larger space than that furnished by any of the other calorimeters. Near the chair calorimeter a special calorimeter with treadmill is shortly to be built.