94 Observations on the Natural History 
period. In six or seven days, he was taken out of the spirits to 
examine the injected vessels ; when casting their eyes on the intes- 
tines, the authors observed, not without surprise, that the alimen- 
tary canal, which, a few days before, was convoluted, soft and 
transparent, had now become not only opake, but so much short- 
ened, that had they wished to describe it, they might have said 
in the language of Cuvier, u qiCil alloit presque en ligne droite 
(Tun bout d V autre?'' This fact, though at first it excited surprise, 
brought with it much satisfaction, since it was easy to compre- 
hend, that the shortening of the alimentary canal was owing to 
the animal having been placed in ardent spirits, while the intes- 
tines yet retained their irritability. Of this opinion they after- 
wards obtained proofs in various ways ; and, in particular, ha- 
ving, on one occasion, opened the abdomen of a living proteus 
for another purpose, they observed the intestines to be at first 
convoluted and transparent ; but under exposure to the air, 
these organs gradually contracted to such a degree, that, at last, 
under the eye, they became knotty and opake, and continued to 
wrinkle and shorten more and more ; so that, after the death of 
the animal, (which occurred in about half an hour,) they were 
brought nearly to a strait line. Instead of spirits, the animal, 
in this its dissected state, was placed in water. On visiting it the 
next day, the alimentary canal was found so much relaxed, as 
to have recovered its former length ; and when the animal, now 
destitute of irritability, was placed in spirits, its intestines main- 
tained their convoluted form, and did not visibly shorten after- 
wards but a very few lines. From these and other facts, the 
authors infer with confidence, that the alimentary canal of the 
proteus is always naturally convoluted ; and that when it is 
seen to proceed in a strait line, it has suffered contraction from 
the action of ardent spirits, or some other agent upon it, while 
still possessed of irritability. 
Experiments similar to the foregoing were tried on the intes- 
tines of the salamander and frog. These animals resist death 
longer than the proteus, and may be considered to possess great- 
er irritability ; but in them the contraction of the intestines was 
not observed to equal, in any degree, that of the proteus, ari- 
sing, probably, from some difference of structure. These obser- 
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