78 VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



BLOOD EXAMINATION. 



Through the kindness of Dr. George R. Minot, we secured the assist- 

 ance of Miss Anna L. Gibson, superintendent of the Huntington Memo- 

 rial Hospital, Boston, and her associate, Miss Myra B. Conover, who 

 made the routine blood examinations of the subjects in both squads 

 from December 19, 1917, to the end of the observations. Here again 

 this series of examinations was unfortunately not begun early enough 

 to secure normal values on Squad A, although they were obtained on 

 Squad B before and during the reduced diet period. Both the red and 

 white blood counts were made with the Thoma-Zeiss counting chamber. 

 The hemoglobin was determined with the Sahli hemometer. It is 

 important to note that the instrument used in this research gave low 

 values for normal blood, i. e., about 85 per cent. 



BODY TEMPERATURE. 



The temperature was taken in the mouth every morning while the 

 men were lying on the couch preparatory to respiration observations 

 at Springfield. These temperatures will not be reported, as they are 

 physiologically of no significance other than to demonstrate that the 

 temperatures were normal. Toward the latter part of the research it 

 was made a general rule to obtain the rectal temperatures when the men 

 were inside the large respiration chamber in Boston, just prior to their 

 rising in the morning. These were made with 12 sensitive clinical 

 thermometers, calibrated with a standard thermometer made by Rich- 

 ter of Berlin. 



During the last few weeks of the research an apparatus for recording 

 the surface temperatures of the skin was installed in the library at the 

 Nutrition Laboratory, with which the temperature of the forehead and 

 of the backs of the hands was taken with a thermo-couple. This 

 thermo-couple consisted of a copper-constantan junction, one end of 

 which was kept in a Dewar flask at approximately 34° C., the tempera- 

 ture being read to hundredths. The other end of the junction, which 

 was in the shape of a hairpin and protected with a thin layer of cotton 

 wadding to prevent the influence of external temperature, could be 

 appHed to the surface of the skin. The thermo- junctions were con- 

 nected with a sensitive Deprez-d'Arsonval galvanometer and the read- 

 ings taken. It was soon found that the deflections of the galvanometer 

 pursued a clearly characteristic course and a point could easily be found 

 which represented in all probability the true skin temperature. These 

 observations were made for all the subjects at various times and quite 

 frequently were controlled by measurements obtained on several mem- 

 bers of the Laboratory staff. Sometimes, also, visitors were measured 

 to assist in the interpretation of the results. 



