1284 PHYSIOLOGY 



The difference between the two salts can be made still more 

 striking if the process of resorption be augmented by increasing the 

 pressure within the tubules by partial obstruction of one ureter. 

 Thus in one experiment, where diuresis was produced by the injection 

 of 30 c.c. of a solution containing 5-85 per cent. NaCl + 14-2 per cent. 

 Na 2 S0 4 , the right ureter was partially clamped so as to make the 



15 



180 



135 



FIG. 534. Curves showing excretion of urine (thick line), of sulphate mole- 



cules [-f^> thin line), and of Cl molecules (f^- K , clotted line), after 

 \ yo ^oo*> 



injection of 50 c.c. of a solution containing 1'775 grm. Cl and 4~8 grin 

 S0 4 per 100 c.c. The black line along the base marks the duration 

 of the injection. (CusHNY.) 



right kidney secrete against a pressure of 30 mm. Hg. The following- 

 results were obtained : 



We must conclude, that the tubular epithelium possesses the 

 power of modifying the glomerular transudate not only by the absorp- 

 tion of water but also by the absorption of dissolved constituents, 

 and that the relative permeability of the cells to the constituents 



