INGESTION OF BEEF TEA. 169 



DISCUSSION OF RESULTS OF BEEF-TEA EXPERIMENTS. 



An examination of the summary of values given for the calorimeter 

 experiments in table 67 (see page 135) shows that there was but little 

 or no increase in the heat output in these experiments. The maxi- 

 mum increment was that on May 9, 1907, of 4 per cent. Furthermore, 

 the figures show no variation as a result of the differences in the tem- 

 perature of the beef tea, nor is there an apparent correlation between 

 the total nitrogen content of the beef tea and the heat increment. 



The beef tea for the respiration experiments, the results of which are 

 summarized in table 68, was made from beef extract in all cases except 

 for the experiment with C. H. H. on February 8, 1911. In prac- 

 tically every experiment there was a perceptible increase in the metab- 

 olism, the maximum being that in the experiment with J. J. C., on 

 January 25, 1911, namely, 12 per cent. The average increment was 

 not far from 8 per cent, a result strikingly at variance with that found 

 in the calorimeter experiments. This is all the more significant as 

 comparatively small amounts were given in the respiration experiments 

 (never more than 400 grams), while in the calorimeter experiments, if 

 we exclude that with J. R., the amount ingested ranged from 892 

 grams to 2,056 grams. As further evidence of the positive increase 

 noted in the respiration experiments, an examination of the detailed 

 results given in tables 95 to 100 shows that the increment in the oxygen 

 consumption was usually still present at the end of the experiment, i. e., 

 the metabolism had not reached the basal level. The values for the 

 total increment here recorded are therefore for the most part smaller 

 than would have been obtained had the experiment been continued. 



The most striking result obtained in these experiments is the very 

 small reaction to the beef tea shown by the subject C. H. H., this being 

 much less than in any of the other respiration experiments in the series. 

 This man was a particularly satisfactory subject with the respiration 

 apparatus, as he lay without movement for hours at a time and showed 

 an unusually clear understanding of the requirements of a cooperating 

 subject. The high values obtained with J. J. C. and V. G. can 

 probably be ascribed to their tendency towards restlessness and lack 

 of cooperation. In any event the results of these respiration experi- 

 ments appear to show that beef tea, when prepared from the so-called 

 commercial extract of beef, has an influence on the metabolism. This 

 effect in certain of the experiments was fairly long continued and 

 amounted at times to an increase of heat approximately 8 to 10 per 

 cent above the basal value. 



The pulse rate was affected to a slight extent in the calorimeter 

 experiments in Boston. Only two of the experiments with the respira- 

 tion apparatus show significant increases in pulse rate, these being the 

 experiment with C. H. H.. February 8, 1911, in which the rate rose 



