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conjecture is, That this animal derives at least a part of its food, if not the whole of it from mineral substan
This opinion appears bold, rather perhaps because we have not been accustomed to think in this manner, than because it is contradicted by experience. It is indeed true, that the greatest part of animals which come under our more immediate observation, draw their principal nutriment either from the ani. mal or the vegetable kingdom ; and because this rule is general we have, perhaps too hastily, concluded it is universal.
Our acute naturalist obseryes, " that we have no clear idea of the manner in which vegetables extract their nourishment from the earth ; yet the fact being so, it might not be unreasonable to suppose, that some animal may derive nutriment by a process somewhat similar.” If we adopt the maxim of Buffon, ' que tout ce qui peut étre est,'(whatever can be, is,) we shall be led to this conclusion. “ When other substances than
stones," Mr Burt-adds, “ shall be discovered in the stomach of this animal, my inference from what I have seen must fall to the ground.” Here, however, we think the concession is too liberal. It may happen that there may be animals, which though they can derive nutriment from mineral substances, may likewise be capable of extracting nutriment from animal or vegetable food. All carnivorous animals, we know, may be brought to live on grain. As just. ly might we then conclude, that if any kind of grain should be found in the stomach of a carnivorous bird, intermingled with animal substances, that this bird derived its whole sustenance from the grain, as that the pangolin could derive no sustenance from the mineral substances found in its stomach, if a single pare ticle of grain should be discovered there.
Setting aside therefore this concession of our author as unnecessary, we proceed. “But if”, says he, “ like other aniinals with muscular and cartilaginous stomachs, this singular quadruped consumes grain, it must be surprising that no vestige of such food was found present in the whole alimentary canal ; nor can it be inferred from the structure of the stomach, that this animal lives on ants or on insects."
He observes farther, from the report of experiments: by signior Brugnatelli of Pavia, on the authori. ty of Mr Crell, “ that some birds have so great a dissolvent power in the gastric juice, as to dissolve in. their stomachs flints, rock chrystal, calcareous stones, and shells : and nothing, we should think, that is so. luble in the stomach of animals, may not be thence: absorbed into the circulating system; and nothing can be so absorbed without affecting the whole, constitution.” But if nature prompts certain animals to. seek with eagerness, and to swallow. with avidity, certain mineral substances, as other ereatures show a natural fondness for animal or vegetable substances, from which we conclude they derive their nou.. Eishment, is it not equally natural to suppose that the first set of animals equally derive nutriment from the substances nature prompts them to choose, as the last ?
He farther observes, that, though Spallanzani found by experiment, when he attempted to feed fowls entirely upon stones, that they died ; yet it can by
po means be inferred from thence, that they derive no nutriment from the stones they naturally pick up We know that man eats salads by choice, and no one will doubt that he derives nutriment from them; yet I question not, that were men to be fed entirely upon salads, for any length of time, very few could. live upon that food alone.
that food alone. Even fresh succulent fruits, which are invariably admitted to be highly nutritious to man, when taken with other food, would, if taken alone, prove fatal to many of the human species : but there can be no doubt that the result of the experiment would prove fatal to the whole human race, should it be conducted in the same manner with those of Spallanzani, on chickens. Were a philosopher, upon dissecting a human stomach, and finding in it some raw vegetables, to try if man could be fed on grass alone, or any other vegetables that came to hand, there can be no doubt but they would all die. How false then would his conclusion be, if from this experiment, he inferred that man could derive no nutriment from raw vegetables ? How infinitely more erroneous would it be to infer, that no other animal could derive nutriment from raw vegetables of any sort !
Fowls, most assuredly, not only swallow, but digest small stones. Manufacturers who use dung of poultry, dever, I believe, find it mixed with stones; but as they require a daily supply of small stones, these must of course, be digested in the stomach, and be absorbed into the lacteals, from whence it is natural to infer, they contribute in one way or other to the health and nutriment of the animal.
From these, and other considerations, our author sees nothing absurd in supposing that the pangolin derives some part, of its nutriment from the mineral kingdom.
I will frankly own that these considerations have had so much weight with me, as to make me believe that we have too hastily adopted the opinion that ani. mals can only derive nourishment from animal or ve. getable substances; and on taking a superficial glance of animated nature, there are innumerable facts pre. 'sent themselves that seem to give weight to this new adopted opinion ; a few of which I shall briefly enu. nierate.
Ist, Live toads have been frequently found in the heart of the most solid stones, where no vegetable or animal substance could come near them. Here mi. neral substances alone would seem to have supporto ed life.
2d, The pholades eats through the most solid rocks, It is true this animal always chooses its habitation in such places as can be moistened, at least at times, with sea water, from which some may suppose it derives its nourishment; but can we suppose it would fhow such a decided fondness for the stone itself, if it derived no kind of sustenance from thence?
3d, Earth worms are not known to gnaw roots of any plants; and are always found full of a slimy earth. They do indeed draw into their holes straws, and other decayed vegetables, which they possibly empley, in a putrified state, as food ; but we have no reason to think that, where these substances are not to be had, the worms would die for want of them.
4th, Sea worms, which are gashered by fishermen for bait, are in like manner full of sand : nor do we know that they ever search for vegetable substances of any sort. Indeed these abound most where nothing of that sort could be had. ~ 5th, Gold and silver fishes, and several other sorts of fishes, can be kept alive for a long time in pure water, in which no kind of animal or vegetable substance can be perceived. On what then do these subsist?
Should it be said they derive their nourishment from small insects they extract from the water, it. would be only putting back, , but not removing the difficulty ; for sțill the question will reçur, on what do these small insects feed ?
I know these fishes will eat bread, if given them, as well as flies, and several other kinds of animal food; but this only tends to show that nature hath endowed them with a power of digesting various kinds of food, Man could live on either flesh, or grain, or succulent fruits or salads; he may be therefore called a carnivorous, a granivorous, a frugivorous or a herbivorous animal. He might be fed upon any one sort ; but he would also take others with avi. dity, if they came in his way, like the poor filhes we treat of.
6th, Is it, however, certain, that man does not de rive sustenance from the mineral kingdom, as well as from the animal and vegetable substances he devours? Does the water he drinks, which is so essentially necessary to his existence, furnish no part of subsistence to him? it seems unreasonable to suppose
it, The following case, among many others, confirms this idea.