NUTRITION LABORATORY. 197 



In the study of the simultaneous fluctuations of body temperature, 24 

 experiments were made, the subjects including five men and one woman. 

 Measurements were obtained of the temperature in the rectum, vagina, and 

 mouth ; also in various superficial cavities, such as in the closed axilla and 

 groin, between the clasped hands, and at various surface points which could 

 be sufficiently closed by flesh to form a temporary cavity. These results are 

 also expressed in the form of curves. The following conclusions are drawn 

 from this series of temperature observations: 



When two thermometers were placed in one internal cavity, neither one 

 less than 6 cm. deep, the temperature curves were parallel and approximately 

 equal. 



When two thermometers were placed in one internal cavity with the dis- 

 tance between them 33^ cm., the outer one being within 5 cm. of the surface 

 of the body, the curves obtained were parallel, but not equal in value, thus 

 indicating a temperature gradient. 



Thermometers placed in the rectum and the vagina, at depths of at least 

 6 cm., showed curves that were parallel and approximately equal. 



Thermometers in the right and left axilla gave curves that were parallel, 

 showing approximately equal temperatures. Like results were obtained when 

 two thermometers were placed in the groin or hand. 



When the subject lay down upon a couch after the slight muscular activity 

 of coming to the laboratory and moving about before the experiment, an 

 initial fall of internal temperature was usually shown. 



Eating, or drinking hot liquids, tended to increase the body temperature, 

 while drinking cold water had a tendency to lower it ; but exposing portions 

 of the surface of the body apparently had no efifect. Muscular exercise pro- 

 duced a marked increase in some experiments, although in others the effect 

 was not noticeable. 



The internal temperature of the body and of the axilla, groin, hand, arm, 

 mouth, and under the breast showed a marked tendency toward parallelism. 



The general conclusion is drawn from the research that, aside from the 

 skin temperature, a rise or fall in temperature of the rectum or vagina is 

 accompanied by an equal rise or fall in temperature of all other parts. 



(10) The determination of the constants of the diflFerential blood-gas apparatus. Joseph 

 Barcroft and H. L. Higgins. Jour, of Physiol., 42, p. 512. 191 1. 



This paper gives a method, which is simpler than any hitherto applied, for 

 determining the constants of the differential blood-gas apparatus described 

 by Barcroft and Roberts (Journal of Physiology, vol. xxxix^ p. 429), these 

 constants being necessary to interpret the readings of a determination into 

 terms of volume of blood-gas liberated or absorbed. Instead of the chemical 

 method of calibration hitherto applied, a physical method is used involving 

 the application of Boyle's law. The method was devised while Mr. Higgins 

 was working with Dr. Barcroft on blood-gas experiments in the physiological 

 laboratory in Cambridge, England. 



