ON THE SECRETION OF SALIVA. 
131 
Here neither the first injection of 200 c.c. NaCl ’2 per cent, into the blood, nor the 
second of 100 c.c., affected appreciably the slow rate of secretion going on at the time, 
owing to the previous dose of pilocarpin ; but the secretion obtained after the first 
injection of NaCl solution, by giving more pilocarpin (III. and IV.) was unusually 
rapid in rate; and it seems to us certain that this was due to the salt solution leading 
to an increased flow of blood through the gland, during the dilatation of the small 
arteries brought about by the additional dose of pilocarpin. At the same time, it is 
possible that after injection of salt solution more pilocarpin passes through the gland 
in a given time, and so helps to increase the rate of secretion. The percentage of 
salts increased in III. nearly as much as it would normally have done. 
There is some difficulty with regard to the percentage of salts in IV., V. In IV. the percentage of 
salts decreases more than normal; in V. it decreases less than normal. It is possible that the former 
was due to a more marked action of the salt solution, and that the latter was due to the breaking up of 
the red blood corpuscles, which about this time gave rise to haemoglobinuria ; possibly, also, from the 
same cause, the percentage of salts in VI. was rather higher than normal, taking I. as a standard. 
The third injection of '2 per cent. NaCl—200 c-c.—trebles the rate of secretion which 
was slowly going on owmg to the previous injection of pilocarpin. The subsequent 
saliva (VI.) obtained by injecting more pilocarpin is rapid, and, judging from other 
experiments, more rapid than it would have been but for the injection of the salt 
solution. 
In the latter part of the experiment, the effect of injecting salt solution is much 
more obvious; it increases the rate of secretion, and decreases the percentage of 
organic substance and of salts. Taking the samples VIII. to XII. we have— 
T.4BLE IX. 
Bate of 
secretion 
per min. in c.c. 
Percentage 
organic 
substance. 
Percentage of 
salts. 
Amount in 
grams of 
organic sub¬ 
stance secreted 
in 100 min. 
Amount in 
grams of salts 
secreted in 
100 min. 
Eemarks. 
VIII. 
•417 
•389 
•572 
•162 
•239 
3 mgrm. pilocarpin in¬ 
jected. 
IX. 
•215 
•905 
•566 
•195 
•122 
After Avithdrawing 160 
c.c. blood, and inject- 
ingSmgrm. pilocarpin. 
X. 
•233 
•464 
•502 
•108 
•177 
After injecting 150 c.c. 
NaCl -2 p.c. 
XI. 
•II7 
•939 
•457 
•110 
•053 
After withdrawing 200 
c.c. blood,and injecting 
3 mgrm. pilocarpin. 
XTI. 
•217 
•374 
•436 
•081 
•095 
After injecting 350 c.c. 
NaCl -2 p.c. 
S 2 
