gestive agents; and, 3. Pancreatic digestion, i. e., the action of the secretion of the pancreas as a digestive agent.
We shall deviate a little from Sir W. Roberts's method of marshaling his conclusions, and shall summarize his results as to the action of the various food accessories on these three acts of digestion continuously.
First, with respect to the action of ardent spirits on digestion. The experiments were made with "proof-spirit" and with brandy, Scotch whisky, and gin; and the conclusion is that, so far as salivary digestion is concerned, these spirits, when used in moderation and well diluted, as they usually are when employed dietetically, rather promote than retard this part of the digestive process, and this they do by causing an increased flow of saliva. "A teaspoonful of brandy or whisky introduced into the mouth can be perceived at once to cause a gush of saliva. The common practice of adding a tablespoonful of brandy to a basin of arrowroot or sago gruel, therefore, promotes its digestion."
The proportion must not, however, much exceed five per cent, and gin seems to be a preferable addition to either brandy or whisky. It was noticed in these experiments that brandy and Scotch whisky interfered with the digestive process, "precipitated the starch more readily," altogether out of proportion to the amount of alcohol they contained, and brandy was worse than whisky; and this circumstance appears to be due to certain ethers and volatile oils in them; and brandy contains a trace of tannin, which has an intensely retarding influence on salivary digestion.
With regard to "peptic" digestion the results are still more surprising. It was found that with ten per cent and under of proof-spirit there was no appreciable retardation, and only a slight retardation with twenty per cent; but with large percentages it was very different, and with fifty per cent the digestive ferment was almost paralyzed.
In the proportions in which these spirits are usually employed dietetically not only do they not appreciably retard digestion, but these experiments show that they "act as pure stimulants to gastric digestion, causing an increased flow of gastric juice and stimulating the muscular contractions of the stomach, and so accelerating the speed of the digestive process in the stomach." For obvious reasons (stated in these lectures) alcoholic drinks as used dietetically can never interfere with pancreatic digestion.
Passing from the consideration of the influence of these ardent spirits on digestion to the more complex problem of the influence of such alcoholic beverages as the various wines and malt liquors, Sir W. Roberts arrives at the following conclusions:
Even very small quantities of the stronger and lighter wines—sherry, hock, claret, and port—exercise a powerful retarding influence