NUTRITION LABORATORY.* 



Francis G. Benedict, Director. 



With the gradual accumulation of apparatus, both purchased and con- 

 structed, the facilities of the laboratory for carrying out projected researches 

 are becoming increasingly valuable, and a larger proportion of time may now 

 advantageously be devoted to research rather than to construction. With 

 apparatus as complicated as is much of that in the laboratory, continual 

 alterations and betterments are to be expected, and all the resources of the 

 laboratory shop are brought to bear upon these important alterations. Coin- 

 cidently the staff of trained assistants is becoming more and more effective, 

 and additions to it are made yearly. The division of funds for the construc- 

 tion of new apparatus, researches in pure physiology, and pathological inves- 

 tigation still remains one of the most important administrative problems. 



ADDITIONS TO EQUIPMENT. 



For the most part the work of the laboratory is now following well-organ- 

 ized lines, and the adjustment of the work to the building and, vice versa, 

 the adjustment of the equipment of the several laboratories to the work, 

 have progressed to such a stage that relatively few major alterations are to 

 be expected. The two balconies added to the calorimeter laboratory have 

 proved most helpful in making use of this large constant-temperature room. 

 Of especial interest is the fact that during the experiment on prolonged fast- 

 ing with a human subject the second balcony was utilized as the living quar- 

 ters of the man when he was not inside one of the respiration chambers. 

 Owing to the construction and isolation of the balcony, it was possible to 

 secure complete control and thus avoid the possibility of the surreptitious 

 taking of food. A balcony has also been added to the room set apart for a 

 psychological laboratory in order to provide more space for psychological 

 research. 



ALTERATIONS IN THE RESPIRATION CALORIMETERS. 



As the result of experimental work during the past year, alterations have 

 been made in the respiration calorimeters, and notable changes introduced in 

 methods and accessory apparatus. Unfortunately, the elaborate self-record- 

 ing device installed with the hope of securing graphic records of temperature 

 differences of the water entering and leaving the calorimeter chamber proved 

 to be wholly unreliable and the manufacturers have been unable to guarantee 



* Situated at Boston, Massachusetts. Grant No. 748. $45,417 for investigations and 

 maintenance during 1912. (For previous reports on work in nutrition see Year Books 

 Nos. 2-10.) 

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