FOOD ACCESSORIES AND DIGESTION. 6 7 



effect, and this superiority of champagne appears to be due to the 

 "mechanical effects of its effervescent qualities." 



The quantity of claret and hock often consumed by many persons 

 at meals must exercise a considerable retarding effect on peptic diges- 

 tion ; but small quantities of these wines (and even of sherry) do not 

 produce any appreciable retarding effect, but act as pure stimulants. 

 These wines, then, may be taken with advantage, even by persons of 

 feeble digestion, in small quantities, but not in large. 



With regard to malt liquors, it was observed, as with wines, that 

 they retarded peptic digestion in a degree altogether out of propor- 

 tion to the amount of alcohol contained in them, and when taken in 

 large quantities they must greatly retard the digestion, especially of 

 farinaceous food ; but a moderate quantity of light beer, when " well 

 up," is favorable to stomach digestion. 



It was proved by these experiments that the sparkling wines 

 impede digestion less than the still ones, and when taken in moderate 

 quantity "act not only as stimulants to the secretion of gastric juice 

 and to the muscular activity of the viscus, but may, at the same time, 

 slightly accelerate the speed of the chemical process in the stomach." 



Next as to the influence of tea, coffee, and cocoa on the digestive 

 processes : 



Tea exerts a powerful retarding influence on salivary digestion, 

 coffee and cocoa a comparatively feeble one. 



Sir W. Roberts estimates the medium strength of the tea usually 

 drunk at four to five per cent ; strong tea may contain as much as 

 seven per cent, weak tea as little as two per cent. Medium coffee 

 has a strength of about seven per cent, and strong coffee twelve to 

 fifteen per cent ; cocoa, on the other hand, is generally weaker, not 

 more than about two per cent, and this, he thinks, may be one reason 

 why it is more suitable to persons with feeble digestions than tea or 

 coffee. 



Tea exercises a powerful inhibitory effect on salivary digestion, 

 and this appears to be entirely due to the large quantity of tannin it 

 contains. 



It appears that tannin exists in two conditions in the tea-leaf. One, the 

 larger portion, is in the free state, and is easily extracted by hot water ; but 

 about one fourth is fixed and remains undissolved in the fully exhausted tea- 

 leaves. Some persons have supposed that by infusing tea for a very short time 

 only two or three minutes the passing of tannin into the infusion icould be 

 avoided. This is a delusion; you can no more have tea without tannin than 

 you can have wine without alcohol. Tannin, in the free state, is one of the 

 most soluble substances known. If you pour hot water on a little heap of tannin 

 it dissolves like so much pounded sugar. Tea infused for two minutes was not 

 found sensibly inferior in its retarding power on salivary digestion to tea infused 

 for thirty minutes. 



One gentleman of my acquaintance (says Sir TV". Roberts) in his horror of 

 tannin was in the habit of preparing his tea by placing the dry leaves on a paper 



