66 THE POPULAR SCIENCE MONTHLY. 



on salivary digestion. This is wholly due to the acid not the 

 alcohol they contain, and if this acid be neutralized, as it often 

 is in practice, by mixing with the wine some effervescent alkaline 

 water, this disturbing effect on salivary digestion is completely re- 

 moved. 



The influence of acids in retarding or arresting salivary digestion 

 is further of importance in the dietetic use of pickles, vinegar, salads, 

 and acid fruits. 



In the case of vinegar it was found that 1 part in 5,000 sensibly 

 retarded this process, a proportion of 1 in 1,000 rendered it very slow, 

 and 1 in 500 arrested it completely ; so that when acid salads are 

 taken together with bread the effect of the acid is to prevent any 

 salivary digestion of the bread, a matter of little moment to a person 

 with a vigorous digestion, but to a feeble dyspeptic one of some im- 

 portance. 



There is a very wide-spread belief that drinking vinegar is an effi- 

 cacious means of avoiding getting fat, and this popular belief would 

 appear from these experimental observations to be well-founded. If 

 the vinegar be taken at the same time as farinaceous food, it will 

 greatly interfere with its digestion and assimilation. 



As to malt liquors, provided they are sound and free from acidity, 

 they interfere but litttle with salivary digestion ; if they are acid, it 

 is otherwise. 



Effervescent table-waters, if they consist simply of pure water 

 charged with carbonic acid, exercise a considerable retarding influence 

 on salivary digestion ; but if they also contain alkaline carbonates, as 

 most of the table-waters of commerce do, the presence of the alkali 

 quite removes this retarding effect. 



" The use of these waters as an addition to wines is," Sir William 

 Roberts observes, " highly commendable," as they " greatly mitigate 

 or wholly obviate the retarding influence of these wines on the diges- 

 tion of starch." 



It was also observed that these weaker forms of alcoholic drinks 

 (wines and beer) differed greatly in their influence on peptic digestion 

 to that of the distilled spirits. They retarded it altogether out of 

 proportion to the quantity of alcohol they contained. Port and 

 sherry exercised a great retarding effect. " Even in the proportion 

 of twenty per cent sherry trebled the time in which digestion was 

 completed." It should further be borne in mind that this wine also 

 greatly retards salivary digestion. Sherry, then, is not a suitable wine 

 for persons of feeble digestive powers. 



With hock, claret, and champagne it was also ascertained that 

 their retarding effect on digestion was out of proportion to the alco- 

 hol contained in them ; but champagne was found to have " a markedly 

 less retarding effect than hock and claret " ; indeed, in the proportion 

 of ten per cent champagne had a distinct, though slight, accelerating 



