NUTRITION INVESTIGATIONS. 41 



results of the application of fertilizers have been marked. Bat ouano 

 secured from caves on the island has triven better results than anv of 

 the commercial fertilizers. 



The cordial support which has been accorded the station b}" the 

 people and legislature of Porto Rico has been very encouraging. 



The details of the work of the stations in Alaska, Hawaii, and Porto 

 Rico may be found in the reports of the officers in charge of these 

 stations, on pages 313, 391, and 419. 



NUTRITION INVESTIGATIONS. 



The nutrition investigations have as hitherto been devoted mainly 

 to a stud}' of the ph^'siological. hygienic, and economic branches of 

 the subject, and have included dietar}- studies and digestion, cooking, 

 and meta))olism experiments. These studies have been carried on in 

 cooperation with universities and experiment stations in California, 

 Connecticut, Georgia. Illinois, Maine, Minnesota, and Tennessee. In 

 cooperation with the Department of the Interior dietary studies were 

 carried on in the Government Hospital for the Insane in the District 

 of Cohunbia. These investigations were inaugurated at the desire of 

 the late Dr. A. B. Richardson, superintendent of the Government 

 hospital, as a part of his general plan for maintaining a high standard 

 for the conditions under which the patients and employees live in this 

 institution. Twentj'-seven dietary studies were made in all with 

 about 1,600 male patients and 125 emplojees. Some of the general 

 results of these investigations are stated in the report of the board of 

 visitors of the hospital to the Secretary of the Interior for 1903, as 

 follows: 



It wa.« noted in connection with these investigations that the food purchased was 

 of goo<l finality; that it was stored, handled, and cooked in a cleanly way, and that 

 the service was a.i good as could be expected under existing conditions. * * * So 

 far as its nutritive value is concerned, the dietary was found to be adequate and 

 reasonably satisfactory. The criticisms made had to do with details rather than 

 with the system as a whole. So far as its cost is concerned, it is higher than seems 

 needful on theoretical grounds, or than that of a similar diet at other institutions. 

 From time to tijae as the dietary studies were in progress, changes were pointed 

 out which woulfi check waste in certain directions, and these were jiromptly acted 

 upon by the late superintendent, who state<l that, in his opinion, as a result of these 

 investigations the cost of the food during the last six months of the year was lower 

 than for any other corresponding period cUiring his connection with the institution. 



Similar studies are being continued this year. A further account of 

 these investigations ma}' ))e found on page 503. 



The work with the respiration calorimeter, carried on atMiddletown, 

 Conn., has been largel}' devoted to the modification and improvement 

 of the apparatus. In its modified form it is possible to make a more 

 accurate determination of cai'bon dioxid and water and a still more 

 important feature, a direct determination of oxygen, which has been 



