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the greater, so that they saw no likelihood but that all the island would be swallowed up; wherefore they unanimously transported themselves to Banda, leaving all their moveables for want of vessels.
On Chylification. By Mr. WILLIAM COWPER. - [1696.]
The cutting-teeth are first employed in dividing the food. When a proportionable piece is thus taken into the mouth, the lower jaw is variously moved by its proper muscles, and mastication is begun, and carried on by the assistance of the tongue, cheeks, and lips; the first two still applying the less divided parts of the aliment to the dentes molares, till there is an equal comminution of all its parts. At the same time several of the muscles, employed in the motion of the lower jaw, are also serviceable in promoting the saliva or spittle, separated from the blood by the parotid glands; those of the lower jaw, and under the tongue into the mouth; the salival glands of the cheeks and lips also contributing their juices, do altogether join with the masticated aliment, before or at the same time it is made fit to be swallowed; which action is called deglutition.
Deglutition is thus performed: the aliment, as well what is fluid as that masticated, being lodged on the tongue, which somewhat hollows itself, by means of its own proper
muscular fibres, for the more commodious entertaining the larger quantity, its tip and sides are applied to the insides of all the teeth of the upper jaw, the tongue is suddenly drawn up by the musculi styloglossi and myloglossus, together with those muscles which pull the os hyoides upwards, at the same time the fauces are also drawn up, and their cavity enlarged by the musculi stylopharyngei; and about two thirds of the superior surface of the tongue is adequately applied to the roof of the mouth; the epiglottis, from its position being consequently depressed, thereby covers the glottis or rimula of the larynx, and prevents any part of the aliment from descending into the windpipe. In this part of the action of deglutition, the glands under the tongue, and excretory ducts of those of the lower jaw, are compressed, and their separated liquors or spittle discharged by their papillæ, situated at the lower part of the frænum or ligament of the tongue ; and this is done by the musculus mylohyoideus. When the aliment is thus forced into the fauces, or upper part of the gula, at the same time the gargareon, with the uvula, are drawn upwards and backwards by the musculisphænostaphyli
, by which means any part of the aliment is hindered from ascending into the foramina narium ; the fauces by the musculus pterygopharyngeus and esophageus are contracted ; by which the aliment is not only compressed into the gula, but the matter separated from the blood by the glands of the fauces, especially of those large ones called tonsillæ, is forced out of their cells or excretory ducts, to join with it in its descent to the stomach by the gula, through which latter it passes, by the action of its muscular fibres.
The aliment, thus impregnated with saliva in mastication and deglutition, being received into the stomach, there meets with a juice separated from the blood by the glands of that part, whose excretory ducts open into the cavity of the stomach : by the commixture of these liquors, whether of the saliva or juice of the stomach, a proper menstruum is composed, by which the parts, of the aliment are still more and more divided, by its insinuating into their pores, by which the air, before imprisoned in their less divided parts, is not only more disentangled, but by the natural heat it must necessarily suffer such a rarefaction, as that the whole stomach becomes still more and more distended : hence it is we have less appetite some time after eating than we had immediately after ; hence also arise those frequent eructations from divers aliments, as old pease, cabbage, and other vegetables. Though we have not used the word fermentation, yet we do not suppose the dissolution of the aliment within the stomach can be done, at least without an intestine motion of its particles with the menstruum : but we have omitted that term, because it may be apt to lead us into an idea of a greater conflict than in truth there really is.
At the same time, when this intumescence and agitation of the matter is made in the stomach, the contents of the neighbouring excretory ducts, viz. the bile in the gall-bladder, the liver ducts, and the pancreatic juice in the ductus pancreaticus, are compressed into the duodenum, through the extension of the stomach itself: the refluent blood of the stomach at that instant being, in some measure, retarded, whence the muscular fibres are more liable to be contracted.
Nor can we conceive how the liquor of the stomach, after uniting with the saliva and aliment, should be still so plentifully excreted from the glands of that part, as to irritate its internal membrane, and excite its muscular fibres to contract, since the muscles of the abdomen would in like manner, as in vomiting, be drawn into a consent of co-operating, and the aliment would be forcibly rejected by the mouth : besides,
should the liquor of the stomach prove so prejudicial in chylification, what would the case be, immediately on the discharge of all its contents. The irritation the stomach undergoes in hunger appears only to arise from an accumulation of the saliva in the stomach, in conjunction with the liquor of the glands of that part ; hence it is we rather discharge the spittle at that time by the mouth, than to suffer any more of it to descend into the stomach ; hence proceeds wliat is called the watering of the mouth; hence, also, when the saliva is vitiated, the appetite is depraved.
The stomach, by means of its muscular fibres, contracting itself, gradually discharges its contents by the pylorus into the duodenum, in which gut, after a small semicircular descent, it meets with the pancreatic juice and bile ; both which joining with it, renders some parts of the aliment more fluid, by still disuniting the grosser parts from the more pure; and here chylification is made perfect. The bile which abounds with lixivial salts, and is apt to mix with the grosser parts of the concocted aliment, stimulates the guts, and deterges or cleanses their cavities of the mucous matter, separated from the blood by glands of the guts, and lodged in their cavities ; which not only moistens the insides of the guts but defends the mouths of the lacteals from being injured by foreign bodies, which often
way. The contents of the intestines moving still on by means of the peristaltic or wormlike motion of the guts, whilst those thinner parts fitted for the pores of the lacteal vessels, called chyle, is absorbed by them, the thicker parts move still more slowly on, and by the many stops they continually meet with by the connivent valves, all the chyle or thinner parts are at length entirely absorbed; the remains, being merely excrementitious, are only fit to be excluded by stool.
Microscopical Observations of vast Numbers of Animalcules
seen in Water. By John HARRIS, M.A. Řector of Winchelsea. — [1696.]
July the 7th, 1694, I examined a small drop of some rainwater which had stood in a gallipot in my window for about two months. I took it with the head of a small pin from the discoloured surface of the water, and observed in it four sorts of animals. In the clear part of the drop were two kinds, and both very small. Some were of the figure of ants' eggs ; these were in continual and swift motion; and I find that this kind of oval figure is the most common to the animalcules found in liquors. The other species, that were in the clear part of the drop, were much more oblong; about three times as long as broad; these were exceedingly numerous, but their motion was slow in comparison of the former.
In the thick part of the drop, for the water had contracted a thickish scum, I found also two species of animals: as, a kind of eels, like those in vinegar, but much smaller, and with their extremities sharper; these would wriggle out into the clear part, and then suddenly return back again, and hide in the thick and muddy part of the drop, much like common eels in the water. I saw here also an animal like a large maggot, which would contract itself up into a spherical figure, and then stretch itself out again; the end of its tail appeared with a forceps, like that of an ear-wig, and I could plainly see it open and shut its mouth, from whence airbubbles would frequently be discharged. Of these I could number about four or five, and they seemed to be busy with their mouths, as if in feeding.
These four kinds of living creatures I found afterwards also in many other drops of the same corrupted water, viz. in its film or scum, which was on the surface ; for under that, in the lower parts of the water, I could never find any animals at all, unless when the water was disturbed, and the surface shaken down into, and mingled with, the lower parts.
April 27th, 1696. With a much better microscope I examined some rain-water, which had stood uncovered a pretty while, but had not contracted any such thick and discoloured scum as that before mentioned had. In this, where it was clear, I could not find any animals at all; but a little thin white scum, which like grease began to appear on the surface, I found to be a congeries of exceedingly small animalcules of different shapes and sizes, much like those produced by steeping barley in water.
At the same time I looked on a small drop of the green surface of some puddle-water : this I found to be altogether composed of animals of several shapes and magnitudes; but the most remarkable were those which I found gave the water that green colour, and were oval creatures, whose middle part was of a grass green, but each end clear and transparent. They would contract and dilate themselves, tumble over and over many times together, and then shoot away like fishes; their head was at their broadest end, for they still moved that way. They were very numerous, but yet so large, that I could distinguish them very plainly with a glass that did not magnify very much. Among these were
interspersed many other smaller and transparent animals, like those just mentioned, as found in the whitish scum that was on some rain-water, which had stood a while uncovered.
April the 29th, 1696, I found another sort of creatures in the water, some of which I had kept in a window in an open glass. They were as large as three of the others, with the green border about their middles, but these were perfectly clear and colourless.
I then also examined more accurately the belts or girdles of
green which were about the above animals, and found them to be composed of globules so like the roes or spawn of fishes, that I could not but fancy they served for the same use in these little animals; for I found now, since April 27., many of them without any thing at all of that green girdle : others with it very much, and that unequally diminished, and the water filled with a vast number of small animals, which before I saw not there, and which I now considered as the young animated fry, which the old ones had shed. I continued looking on them at times, for two days, during which time the number of the old ones, with the green girdles, decreased more and more ; and at last I could not see one of them so encompassed, but they were all clear and colourless from end to end.
May the 18th, 1696, I looked on some of the surface of puddle-water, which was bluish, or rather of a changeable colour, between blue and red. In a large quantity of it I found prodigious numbers of animals, and of such various sizes, that I could not but admire their great number and variety; but among those were none with those girdles before mentioned, either of green or any other colour.
I then also examined the surface of some other puddlewater, that looked a little greenish ; and this I found stocked with such infinite numbers of animals as I never yet saw, except in the genitura masculinâ of some creatures. Among these there were many of a greenish colour, but they all moved about so swiftly, and were so near to each other, that I could not distinguish whether the green colour were all over their bodies, or whether it were only round their middles in girdles, as before ; but from the roundness of their figure and their smallness, I judged that they chiefly consisted of the young animated spawn of the above-mentioned kind of animals. I found that the point of a pin dipped in spittle would presently kill them all.
In the surface of some mineral chalybeate water, which had stood in a phial unstopped for about three weeks, I saw two