ii4 



Scientific Proceedings (65). 



Respiration was studied by determining its rate and the volume 

 of air respired, the carbon dioxide tension of the alveolar air by the 

 Haldane method, and the volume of the dead space by the method 

 of Douglas and Haldane, while the acidity of the blood was tested 

 by means of both the carbon dioxide tension of the alveolar air 

 and the dissociation curve of the hemoglobin by the method of 

 Barcroft. By the usual methods determinations were made of 

 the respiratory quotient, the amounts of carbohydrate and protein 

 metabolism, the production of heat, and the specific gravity and 

 freezing-point of the urine. Some determinations of the sensi- 

 tivity of the skin were made by the method devised by Martin. 



Appetite was studied by measurements of the number of 

 calories represented in the food actually eaten by each subject from 

 standard luncheons which were served in the observation room. 

 The amount and the quality of mental work which each subject 

 was capable of performing under the different atmospheric con- 

 ditions were determined by means of a considerable variety of 

 mental tests, such as the naming of colors and their opposites, the 

 cancellation of given letters in a large group, the addition of 

 numbers, mental multiplication, typewriting, the grading accord- 

 ing to a given scale of specimens of handwriting, poetry, and 

 English prose composition. 



The action of the different atmospheric conditions upon the 

 nasal mucous membrane was observed by means of rhinoscopic 

 observations of the membrane, which were supplemented by the 

 use of the Zwaardemaker plate. The significance of dust in the 

 air in relation to infection was studied by exposing animals for 

 stated periods to air containing dust from various sources, such 

 as metal, hair, coal and mother-of-pearl, and subsequently inocu- 

 lating the animals with the bacilli of tuberculosis. By means of 

 an apparatus specially devised the amount of dust in the air 

 under different conditions has been determined. The relation of 

 atmospheric conditions to immunity has been studied by deter- 

 minations of the agglutinins in the blood. 



