8 Influence of Inanition on Metabolism. 



METHOD OF INVESTIGATION. 



In any study of metabolism, the greater the number of series of simultaneous 

 observations on the same person, the more nearly does the study approximate 

 completeness. The number of factors which may be determined is limited by 

 the conditions surrounding an experiment, and while the use of the respiration 

 calorimeter enables us to secure data heretofore not attainable, the nature 

 of the apparatus is such as to preclude many physical and psychical obser- 

 vations which might have been obtained on a subject living outside the chamber 

 of the respiration apparatus. 



The observations made in these studies naturally divide themselves into four 

 classes grosser or general observations, and physiological, chemical, and 

 physical measurements. The following sections enumerate the observations 

 themselves and the methods employed in obtaining them. 



GROSSER OBSERVATIONS. 



In all of the instances of prolonged fasting which have been observed by 

 scientists, certain grosser observations have been made which deal for the most 

 part with the physical appearance, loss in weight, and general mental and 

 physical condition. Such observations were likewise made in connection with 

 the series of experiments here reported, although, as has been pointed out 

 above, they were made, at times, with considerable difficulty. 



Body-weight. By means of the special form of weighing apparatus described 

 in an earlier report, 31 accurate observations on body-weight were possible in 

 all save the first experiment. Use is made of the fluctuation of the body- 

 weight not only to note the condition of the subject but also as a check upon 

 the accuracy of the determinations of intake and output. The total weight of 

 income and the total weight of outgo being known, the difference between them 

 may be determined and should represent body substance gained or lost; this 

 could be readily checked by means of the weights recorded by the special 

 apparatus for obtaining body-weight. 



Examination by physician. In a study of fasting involving abstinence 

 from food for a number of days, it was deemed important to have careful 

 examinations made of the subject from time to time by a skilled physician; 

 consequently it was arranged to have Dr. John E. Loveland, of Middletown, 

 Connecticut, make careful examinations of all the subjects of these experi- 

 ments, and also to examine the subjects of long experiments on each day of the 

 experiments proper. The observations of the physician were for the most 

 part confined to those obtainable through a glass window and by the telephone, 

 although he could make use of the continuous record of body temperatures 

 obtained during the experiments. Several attempts were made to determine 



31 Carnegie Institution of Washington Publication 42 (1905). 



