54 STUDIES IN DIGESTION 



quantity of food-stuffs, the whole theory of feeding 

 by nutrient enemata would collapse. 



In the experiments described above, Groves and 

 Walker Hall found that the absorption of nitrogen 

 and fat by the colon was so small as to be negligible. 

 Laidlaw and Ryffel, analysing the urine during rectal 

 feeding, found that the nitrogen output corresponded 

 pretty closely to the published figures for pro- 

 fessional fasting men at the same date of starvation ; 

 the enemata used were, however, not particularly 

 suitable, consisting of the whites of nine eggs, six 

 ounces of raw starch, and twenty-four ounces of 

 peptonized milk. The albumin and starch were 

 probably not touched. Langdon Brown found no 

 difference in the urea of the urine whether the patients 

 were given peptonized milk or normal saline. Further 

 observations on these lines, using dextrose and 

 adequate quantities of milk, either peptonized or 

 even converted into aminoacids by prolonged 

 digestion, are greatly needed. 



Sharkey and others claim that a good deal of 

 nitrogen can be absorbed by the rectum, basing their 

 findings on the analysis of rectal washings ; but this 

 method is open to criticism, as sometimes, in spite of 

 washing out, the patient may pass an enormous 

 putrid evacuation, showing that the lavage was not 

 effectual. 



I am kindly permitted to quote some unpublished 

 analyses, which will be found in the Appendix, made 

 by Dr. R. E. Thomas on patients of Dr. Nixon's, in 

 the Bristol Royal Infirmary. A daily estimation of 

 the output of urea and ammonia nitrogen, and also 



