NUTRITION LABORATORY. l6l 



A small subsidiary brine coil permits the regulation of the temperature of a 

 current of water used to bring away heat from the calorimeters. 



Facilities for Experiments on Animals. — A special suite of rooms on the 

 third floor is provided for metabolism experiments on animals. In order to 

 prevent the odors from the animals reaching the rest of the building, each 

 room in which animals are kept or in which they are experimented upon is 

 provided with a special skylight with large windows opening directly on to 

 the roof. The roof has a high parapet and offers an admirable opportunity 

 for keepng small animals out of doors a good part of the year. The elevator 

 extends to the roof, so that animals can be carried from the animal rooms to 

 the roof without difficulty. 



Photographic Room. — The large amount of new apparatus and peculiar 

 features of experiments of the nature carried out in this laboratory necessitate 

 some suitable place for taking photographs. Hence a photographic room, 

 with a specially well-lighted bay and a dark-room with all proper facilities, 

 was placed on the third floor. Heavy mains from the switchboard are con- 

 nected with a stage plug in this room, allowing abundant current for an arc 

 lamp for micro-photographic work. 



Equipment. — The machine-shop is equipped with an engine lathe, a milling 

 machine, and minor lathes and machines, thereby enabling us to do a very 

 large proportion of our work in the building. The installation of this shop 

 was especially planned so as to permit us to cooperate to mutual advantage 

 with two experimental machine-shops belonging to the medical school. It is 

 thus possible for us to construct all apparatus without the delays incidental to 

 repairs and construction in an instrument-shop. 



As a result of a careful investigation of foreign laboratories, a large num- 

 ber of interesting and important details in the equipment of the chemical lab- 

 oratories have been introduced, and it has been found that a very large sav- 

 ing in time and expense may be made by constructing laboratory desks, 

 tables, wall-cases, and shelving as needed, rather than attempt to install with 

 an initial contract. 



With reference to the equipment of the respiration calorimeter laboratory, 

 it may be said that at the time of the closing of this report one respiration 

 calorimeter has been built and completely tested and 12 experiments made 

 with it. A second is rapidly nearing completion. 



A large amount of apparatus specially u^ed for studying problems in nutri- 

 tion has been purchased from various laboratories abroad, and it is believed 

 that there exists nowhere so complete a collection of special apparatus of this 

 type as has been assembled in the Nutrition Laboratory. 



The advantage of keeping in close touch with European and American in- 

 vestigators in similar lines by means of periodical tours of inspection has 

 proven of incalculable benefit in the equipment of the laboratory. It has been 



