76 A STUDY OF THE INFLUENCE 



It is an observation easily verified, that the presence of a 

 small quantity of strong alcohol or alcoholic beverage in the 

 mouth excites a sudden flow of saliva. This acceleration in 

 flow is, at most, a very brief one, and the rate of flow quickly 

 returns to that pertaining to normal conditions, i. ., absence 

 of stimuli in the mouth. The stimulation in this case is not 

 due merely to the mechanical action of the fluid introduced, 

 nor is it a form of stimulation specific for alcohol alone, as our 

 experiments on dogs have demonstrated. Thus, animals were 

 anaesthetized with ether and chloroform through a tracheal 

 cannula (thereby avoiding direct stimulation of salivary flow), 

 a small dose of morphine, or a larger one of chloral, having 

 been previously administered. A cannula was then introduced 

 into one or both ducts of the submaxillary glands. A small 

 wad of absorbent cotton moistened with the fluid to be studied 

 was introduced with a forceps into the back of the mouth 

 upon the tongue, and the flow of saliva from the ends of the 

 cannulas noted. It was found by this method that water or 

 weak sodium chloride solution (0.7 per cent) produced no 

 further effect than the secretion of a drop or two of saliva due 

 to the mere mechanical action of introducing the wad ; with 

 increasing strengths of salt the secretion was decidedly ac- 

 celerated, flowing readily after application of 20 per cent salt 

 solution, the acceleration, however, being very brief in dura- 

 tion (5 min.). The buccal cavity could be swabbed out with 

 water occasionally, the effect being a minimal one. It was 

 found that weak alcohol, introduced in this way, provoked 

 little, if any, flow ; while stronger alcohol (50 per cent) gave 

 rise to a transitory secretion, the stimulation in this case, how- 

 ever, being far more marked than can be produced by the 

 indirect action of alcohol through the stomach. Thus, in one 

 animal, in which the activity of the glands was found pro- 

 nounced when a drop of dilute acetic acid was applied to the 

 tongue, injection of 100 c.c. 50 per cent alcohol directly into 

 the stomach, failed to provoke any reflex salivary flow in half 

 an hour. 



Turning now to the influence of alcoholic fluids upon the 



