188 PHYSIOLOGY. 



different substances ; as it seems at certain times to dissolve 

 the one more readily than the other. What this depends upon, 

 or under what different modifications it may appear, we cannot 

 at present venture to determine. 



" At present it seems further necessary to remark, that with 

 respect to perhaps every human stomach, the powers of it in 

 general being given, there is a difference in the solution of dif- 

 ferent substances, arising entirely from the different texture of 

 these. Thus it appears, that apple and melon are less readily 

 soluble than strawberries and raspberries ; that full grown cab- 

 bage is less soluble than cauliflower ; and a like difference may 

 be observed with respect to many other vegetable substances, 

 as we shall hereafter take notice of more particularly. In the 

 mean time it may, in illustration of the whole, be in general 

 observed, that in many vegetables there is a different solubility 

 in the different parts of them ; so that, in one and the same, 

 while a certain part of .them is -entirely dissolved, another part 

 of them passes off by stool in a very entire state. Thus, as 

 many fruits consist of a tender pulp enclosed in a firmer mem- 

 brane or husk, so the solubility of the whole will depend upon 

 the proportion of these parts ; and as, in the maturation of fruits 

 their pulp goes on increasing, while their membranes are con- 

 stantly growing thinner and tenderer, so in many instances the 

 solubility of fruits taken in an entire state will commonly be in 

 proportion to their maturity. 



" In illustration of this subject of the solubility of aliments, it 

 may be remarked, that in so far as the arts of cookery render 

 the texture of aliments more tender, it renders them in propor- 

 tion more soluble in the stomach. 



" At entering upon this subject, I should have observed, that 

 we have a particular proof of the more ready or difficult solu- 

 bility of different substances in the stomach. There are men 

 who are occasionally, and many who are very frequently, liable 

 to a rumination, or the bringing up, by an eructation, a part of 

 the contents of the stomach. These parts are frequently some- 

 what entire portions of vegetable or animal matters, which are 

 manifestly of a firmer texture than the rest which had been 

 taken down, and have not therefore been so readily dissolved. 

 From the rarefaction of their air not entirely extricated, they 



