126 
MESSES. J. N. LANGLEY AND H. M. FLETCHER 
An example' of the effect of dyspnoea, when the saliva is obtained by injecting pilo- 
carpin, is given in Experiment 7. 
Table VIT. 
Rate of 
secretion 
per minute, 
in c.c. 
Percentage 
of 
organic 
substance. 
Percentage 
of salts. 
Saliva obtained by 
VI. 
-.360 
1-547 
•529 
Pilocarpiu and stimulating chorda. 
VII. 
•250 
•446 
•474 
Pilocarpin. 
VIII. 
•:3II 
-517 
•557 
More pilocarpin during dyspnoea. 
There is here an increase in the percentage of salts during dyspnoea, but the results 
are complicated by the earlier procedure in the experiment. 
Dyspnoea appears also to have an after-effect, tending to increase the percentage 
of salts, and possibly also of organic substance, in the saliva subsequently secreted; 
but this after-effect is not great and soon disappears. 
The prominent effect of not too prolonged dyspnoea is that, whilst 
decreasing the rate of secretion of saliva, it increases the percentage of 
salts, and tends to increase the percentage of organic substance in the 
saliva. 
Effect of Clamping the Carotid. 
When one carotid is clamped, the blood flow through the sub-maxillary gland is, as 
is well known, not stopped, but simply diminished, the degree of diminution varying 
in different cases. We have tried the effect of clamping the carotid on the composi¬ 
tion of saliva in a few cases only; the effect, however, is marked: clamping the 
carotid increases the percentage of salts in saliva hoth during the pteriod 
of clamping and for a short time afterwards. 
