388 
DIGESTION VISIBLE TO TIIE EVE. 
had been somewhat more rapid in than out of the stomach. But 
this experiment is remarkable in another point of view, as 
shewing, that in the short space of twenty minutes, enough of 
gastric juice had been secreted for the entire completion of 
digestion. 
“ With a view to verify these results, and also to discover the 
comparative digestibility of different kinds of aliment. Dr. 
Beaumont gave St. Martin for dinner eight ounces of recently- 
salted lean beef, four ounces of potatoes, some bread, and four 
ounces of boiled turnips. After fifteen minutes he withdrew a 
portion of the contents of the stomach, and found that some of 
the meat had already been slightly digested. In a second por- 
tion, withdrawn at the end of forty-five minutes, fragments of the 
beef and bread were perceptible, and in a still more advanced 
state of digestion ; the meat was in small shreds, soft and pulpy, 
and the fluid containing it had become more opaque and gruel- 
like in appearance. When two hours had elapsed, a third 
quantity was taken out, at which time nearly all the meat had 
become chymified and changed into a reddish-brown fluid ; but 
small pieces of vegetable matter now presented themselves for the 
first time, but in a state of digestion so much less advanced than 
the meat, that their peculiar structure was still distinctly visible. 
JSome of the second and third portions, put into a vial and treated 
in the usual way, advanced to complete digestion, as in the 
other experiment, except that the process was slower, and that a 
few vegetable fibres remained to the last undissolved ; thus con- 
firming the general opinion, that vegetables are more difficult of 
digestion than animal substances. 
“ Such being the influence of gastric juice on different ali- 
ments at the natural heat of the body, we have now to ascertain, 
in the second place, what share the high temperature has in 
the result. To determine this point, Dr. Beaumont took out two 
ounces of gastric juice, and divided it into two equal portions, 
in separate vials. He added to each an equal weight of masti- 
cated fresh beef ; and placed the one in a bath, at the temperature 
of 99°, and the other in the open air, at 34°. As a contrast to these, 
he placed beside the latter a third vial, containing the same 
weight of masticated meat in an ounce of clear water. 
“ In two hours the meat in the warm vial was partially digested ; 
that in the cold gastric juice was scarcely changed ; and the third 
portion, in the cold water, seemed only a little macerated. In 
six hours the meat in the warm vial was half digested, while that 
in the two others had undergone no further alteration. The 
gastric juice in the first vial having by this time dissolved as 
much as it could of the beef, four drachms more were added 
