128 
MESSRS. J. N. LANGLEY AND H. M. FLETCHER 
It will be seen on comparing I. and II. that clamping the carotid increases the 
percentage of salts from '499 to ‘512, although the rate of secretion falls from 
1’55 c.c. to ’50 c.c. a minute; so also in IX., clamping the carotid during dyspnoea 
increases the percentage of salts considerably more than does dyspnoea alone (VIII.). 
It will be seen also that clamping the carotid has a very great after-effect; this is, 
in fact, in III. and V. greater than the effect whilst the carotid is clamped; thus m 
III., collected after removing the clamp from the carotid, the percentage of salts rises 
from '512 to '674, whilst the rate of secretion falls from ‘5 c.c. a minute to *128. 
That the after-effect is slight on clamping for the third time may have been due to 
the much longer duration—half-an-hour—of the closure of the carotid. 
Clamping the carotid increases also somewhat the percentage of organic substance 
above that which corresponds to the rate of secretion of saliva [cf. VIII. and IX.). 
A similar result was obtained in Experiment 8. 
Table VIII. 
Secretioia obtained by injecting pilocarpin. 
Rate of secretion 
per minute in c.c. 
Percentage of 
salts. 
Remarks. 
I. 
•675 
•559 
11 . 
•250 
•420 
VII. 
•333 
•660 
Dyspnoea, carotid clamped. 
VIII. 
■417 
•572 
Collected 8 min; after unclamping carotid. 
The Effect of Loss of Blood. 
The details with regard to this are given on p. 130, together with the effect of 
injecting dilute salt solution into the blood. It will be seen that bleeding decreases 
the rate of secretion and increases the percentage of organic substance 
in the saliva. The rate of secretion of salts falls, but its percentage is 
greater than that which corresponds to the rate of secretion of the 
saliva. 
The Effect of injecting dilute Salt Solution into the Blood. 
When dilute salt solution is injected into the blood, the percentage composition of 
the blood is, of course, altered. To the eye, the tissues, especially the abdominal 
viscera, become more flushed, and the veins fuller. According to Worm-Muller 
and others, increasing the volume of the blood 20 to 50 per cent, by transfusion 
causes no increase of arterial blood pressure, except for a brief time immediately after 
