NUTRITION LABORATORY. 279 



furnish a complete picture of the total energy changes during this form 

 of exercise. 



The investigation has covered rates of progression from a very slow 

 saunter of 35 meters per minute to a brisk pace of 100 meters per 

 minute and from a zero grade to one of 45 per cent. At the higher 

 grades it was, of course, impossible to maintain the greatest speeds. At 

 the point of 40 per cent grade and 65 meters per minute speed, the 

 subject consumed oxygen at the rate of 3,159 c. c. per minute, while 

 3,030 c. c. of carbon dioxide were ehminated. Electrocardiograms 

 were taken at frequent intervals during the muscular activity. It has 

 thus been possible to get authentic photographic records of the pulse 

 during the muscular work, as well as of the changes during the transi- 

 tion from mild to vigorous exercise and the reverse. The Bock-Thoma 

 oscillograph, used for this purpose last year, was replaced by a Cam- 

 bridge string galvanometer, as the war made it impossible to secure 

 certain broken parts of the former instrument. The records with the 

 string galvanometer were equally satisfactory and the expense of photo- 

 graphic supplies was materially reduced ^^0-^4 



During the latter part of the investigation measurements were also 

 made of the body-temperature by means of a rectal resistance-ther- 

 mometer and a galvanometer ; curves showing the changes in the body- 

 temperature during work were thus simultaneously secured. Other data 

 recorded during the study included the number of steps per minute, 

 the height to which the body was lifted per minute, the respiration-rate, 

 the volume per respiration, and the changes in blood-pressure. Through- 

 out the entire investigation the treadmill, constructed in this Laboratory 

 in 1912, gave excellent results. It is now being thoroughly examined 

 and tested in preparation for use in the large respiration calorimeter. 



METABOLISM IN RECTAL FEEDING WITH ALCOHOL AND SIMPLE SUGARS. 



As a part of the research upon the physiological effect of ethyl 

 alcohol in man, begun by this Laboratory, an extensive investigation 

 of the use of alcohol in rectal feeding has been made by Dr. T. M. 

 Carpenter. Four healthy medical students acted as subjects. Ethyl 

 alcohol in concentrations of 5, 7.5, and 10 per cent in water has been 

 injected per rectum in quantities varying from 250 c. c. to 1,000 c. c. 

 of the diluted alcohol. In most of the tests 25 grams of the alcohol 

 were used, although in som.e instances as much as 50 grams were given. 

 The amount unabsorbed w^as determined by the so-called "wash out" 

 method. The effect upon the character and amount of the total 

 metabolism was found by determining the gaseous exchange with the 

 Tissot respiration apparatus. By the appUcation of a mask it was 

 possible to measure the gaseous exchange continuously for 5 hours in 

 periods of from 10 to 15 minutes. The total amount of air expired each 

 period and its composition were determined. From these the total 



