Kidney Hypertrophy 453 



subsequent paper. Hypertrophy of the kidneys existed without 

 hypertrophy of the heart. The ratio of the weight of the heart 

 as well as of the liver to the body weight was about the same 

 in the animals fed the high protein diets as in the control ani- 

 mals. The ratio of the weight of the kidneys to the body weight 

 in the animals on the high protein diets was, on the average, 

 almost double that of the control animals. The hypetrophy oc- 

 curred whether the protein used was of animal or vegetable 

 origin or was rich or poor in phosphorus. 



The animals on such diets were poorly or, at best, only mod- 

 erately well nourished. The subcutaneous fat was scant and 

 the skin adherent. There was some fat in the abdominal cavity 

 and in certain animals it was fairly plentiful, but in none 

 was it so abundant as in the control animals. In a con- 

 siderable proportion of the animals the lungs showed the in- 

 fection so commonly seen in the domestic rat. The thymus was 

 invariably atrophied. The heart was normal. The spleen varied 

 greatly in size. In some rats it was large, in others normal, and 

 in others atrophic. The liver presented no gross abnormalities. 

 The testes in some of the animals were normal in size; in others 

 they were exceedingly atrophic. 



227 (2187) 



A contribution to the bio-physics of intestinal absorption. 

 By J. S. VAN DER LINGEN and D. I. MACHT. 



[From the Pharmacological Laboratory, Johns Hopkins Univer- 

 sity, Baltimore, Md.] 



The following experiments were suggested by purely bio- 

 physical considerations concerning absorption from the intes- 

 tines and it was deemed desirable to report the same in this pre- 

 liminary communication. 



On purely physical-chemical grounds it can be shown that the 

 absorption of a chemical in solution which flows through a 

 membranous tube will depend on the speed of flow of the solu- 

 tion through the lumen of the tube. The authors attempted to 



