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mended by their fleeces, the ancon breed seems in danger of becoming almost extinct. They have so much declined, that, for many months, it was not an easy matter for me to procure one for dissection in Boston. That operation was performed by the ingenious Dr. SHATTUCK, who makes the following remarks.

“ The sheep weighed just before it was killed forty-five “ pounds. The most obvious difference in its skeleton from “ the skeleton of the common sheep, so far as my superficial “ observation has extended, consists in the greater looseness of the articulations, the diminished size of the bones; but “ more especially in the crookedness of its forelegs, which “ causes them to appear like elbows, while the animal is walk

ing. I have taken the liberty to call them ancon, from the “ Greek word which signifies elbow. On dissecting the sheep, "I could not forbear noticing the comparatively flabby condi“ tion of the subscapularic muscles: this may partially account “ for the great feebleness of the animal, and its consequent “ quietude in pasture.”

This skeleton will be presented to the President of the Royal Society, by the hand of the gentleman who is so obliging as to charge himself with the delivery of this letter.

I have been the more particular in the statement, because I deemed it important the point should be settled, so far as evidence can be adduced, that the preservation of different breeds, once clearly designated, in whatever manner obtained, whether from casualty, as in the present instance, or from calculation and cultivation, as in that of the new Leicester breed, depends more on some inherent quality in the blood, than on climate, food, or any other circumstance. Although it is allowed

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that these have no inconsiderable influence, particularly the first, on the fleece, in the torrid zone. In all temperate regions, and even in the higher latitudes, where extreme cold prevails, flocks may be improved by care, or deteriorated by the want of it.

The settlement of this point would not fail to have a tendency to eradicate the remains of the pernicious prejudice, that the Merinos of Spain cannot be bred out of that country, without degenerating and losing their essential character for wool.

The beneficent Creator having ordained “ that all creatures shall increase after their kinds,” has still left much for man to do, in regard to those which are made more immediately subservient to his use.

We are not ignorant how much the agricultural nations of Europe and America are indebted for meliorations in their husbandry to modern researches and discoveries in chemistry, natural history, and other branches of philosophy; as well as to experiments of eminent farmers, and especially breeders of cattle.

My experience has been too limited for me to flatter myself with being able to add to the stock of materials for investigation and improvement, except by becoming in some degree the medium of communication between the agriculturalists of the two continents.

I have formerly exerted myself to enable my countrymen to improve their breeds of useful animals, perhaps not altogether without success. My present object should rather be, to supply facilities and inducements for abler men, possessed of better opportunities, to discover and disclose the best means

for selecting and spreading the most approved breed of fine woolled sheep, by which Merinos are meant, throughout the different countries which are known to be well adapted to their cultivation.

So tempting a motive for contributing my mite to the repertory of a Society, justly celebrated for the extension of human knowledge and improvements, and which has done me the honour to enrol my name in their number, was not to be resisted; and the less, as it affords me occasion of

presenting, at the same time, the homage of high respect for their President, with which I have the honour to be, Sir, your most obedient servant,

D. HUMPHREYS. XII. Experiments to ascertain the coagulating Power of the Secretion of the gastric Glands. By Sir Everard Home, Bart.

, F.R.S. Communicated by the Society for promoting the Knowledge of Animal Chemistry.

Read January 21, 1819.

In attempts to investigate the process of digestion in quadrupeds, the difficulties are almost insurmountable; the gastric glands are scarcely perceptible, and occupy a small portion of the stomach, every other part of the inner membrane is throwing out secretions of a different kind, and these are all mixed together with the food in the general cavity. Under such circumstances, the properties of the secretion of the gastric glands can never be ascertained, since it cannot be procured in a pure state. It is generally allowed, that the first process the food undergoes in the stomachs of animals is being converted into a jelly; but whether this is produced by the gastric liquor as the previous change to dissolution, or whether it takes place before that liquor is applied, has not been ascertained.

Mr. HUNTER made many experiments upon the coagulating power of the secretions of the stomach, which establish the fact of coagulation taking place in the stomachs of animals of different classes.

An infusion of the dried inner membrane of the fourth cavity of the stomach of the calf, being in common use for

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the purpose of coagulating milk, proves, that every part of that membrane possesses such a power.

Mr. HUNTER ascertained, that the mucus found in the first, second, and third cavity of the calf's stomach, dissolved in water, had no power of coagulating milk, while a solution of the mucus of the fourth cavity possessed that property, and retained it even after it had been so long kept, as to begin to become putrid.

When the calf has left off sucking, and is old enough to be killed for veal, the inner membrane of the fourth cavity of the stomach readily coagulates milk.

If different portions of the inner membrane of the hog's stomach are prepared as rennet, no part coagulates milk but that near the pylorus, and I have shewn, in a former paper, that the gastric glands are situated there.

The crop and gizzard of a cock were prepared as rennet, milk was coagulated in half an hour by that of the gizzard, in two hours by that of the crop.

The contents of a shark's stomach coagulated milk immediately; portions of the stomach washed and steeped sixteen hours in water, formed a solution which produced the same effect.

Rennet made from the stomach of a salmon coagulated milk in four or five hours; when made from the stomach of the thornback, it produced the same effect.

These experiments shew, that the secretions of the stomach have a power of coagulating milk; they do not, however, explain whether this power belongs to any one secretion in particular, or to a mixture of them all. With a view to ascertain to what particular secretions this

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MDCCCXIII.

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