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spheroid would have a fixed position, and that it would be always high water under the poles, and low water every where under the equinoctial ; and, therefore, the nearer the moon approaches to the poles, the less is the agitation of the ocean, which is the greatest of all, when the moon is in the equinoctial, or farthest distant from the poles. Whence the sun and moon, being either conjoined or opposite in the equinoctial, produce the greatest spring-tides ; and the subsequent neaptides, being produced by the tropical moon in the quarters, are always the least tides ; whereas in June and December, the spring-tides are made by the tropical sun and moon, and therefore less vigorous ; and the neap-tides by the equinoctial moon, which therefore are the stronger : hence it happens, that the difference between the spring and neap tides in these months is much less considerable than in March and September. And the reason why the very highest spring-tides are found to be rather before the vernal, and after the autumnal equinox, viz. in February and October, than precisely upon them, is, because the sun is nearer the earth in the winter months, and so comes to have a greater effect in producing the tides.
A Discourse concerning the Large Horns frequently found under
Ground in Ireland. By THOMAS Molyneux, M.D. By the remains we have of this animal, it appears to have been of the genus cervinum or deer kind, and of that sort that carries broad or palmed horns, bearing a greater affinity with the buck or fallow deer, than with the stag or red deer, that has horns round and branched without a palm : this I lately observed, having an opportunity of particularly examining a complete head, with both its horns entirely perfect, not long since dug up, given to my brother William . Molyneux, as a natural curiosity.
“I have by the bearer sent the head and horns I promised you:
: this is the third head I have found by casual trenching in my orchard: they were all dug up within the compass of an acre of land, and lay about four or five feet under ground, in a sort of boggy soil. The first pitch was of earth, the next two or three of turf, and then followed a sort of white marl, where they were found.”
I took their dimensions carefully as follows: from the extreme tip of the right horn to that of the left, expressed in the line AB, was 10 feet 10 inches; from the tip of the right horn to the root where it was fastened to the head, CD, five
feet two inches ; from the tip of the highest branch, measur. ing one of the horns transverse, or directly across the palm,
to the tip of the lowest branch, EF, three feet seven inches and a half. The length of one of the palms, within the branches, GH, two feet six inches : the breadth of the same palm, still within the branches, IK, one foot 10} inches: the branches that shot forth round the edge of each palm were nine in number, besides the brow-antlers, of which the right antler, DL, was a foot and two inches in length, the other was much shorter: the beam of each horn at some distance from the head, where it is marked M, was about two inches and six tenths of an inch in diameter, or about eight inches in circumference ; at the root, where it was fastened to the head, about 11 inches in circumference. The length NO of the head, from the back of the skull to the tip of the nose, or rather the extremity of the upper jaw-bone, two feet, the breadth of the skull PQ, where largest, was a foot.
Another such head, with both the horns entire, was found some years since buried 10 feet under ground in a sort of marl. And in the year 1691, Major Folliot told me, that digging for marl near the town of Ballymackward, not far from Ballyshannon, in the county of Fermanagh, he found buried, 10 feet under plain solid ground, a pair of this sort of horns, which he keeps still in his possession. In the year 1684, two of these heads were dug up near Turvy, within eight miles of Dublin. Not long since, a head of this kind, with its horns, was found near Portumny, the house of the Earls of Clanricard, seated on the river Shannon, in the county of Gallway. And to my knowledge, within less than 20 years, of the ossa pubis, that at their basis here they touch each other, just at the coalition of the bones that form the ossa pubis. The other extremities of these bones were at a disstance from one another, that measured 2 inches. The basis of these bones where joined to the ossa pubis was half an inch broad, having two heads; the larger lying near the coalition of the ossa pubis, and the lesser towards the os coxendicis ; having in the middle a sinus, into which was received a protuberance of the ossa pubis; by which contrivance it appears there can be no motion of these bones, nearer or farther from one another, but that they must stand always at an equal distance ; but they were capable of a small motion inwards towards the spine, and outwards from it. These bones, as they ascended from the os pubis, grew slender, being about the middle but a quarter of an inch broad; and they were each two inches long. These bones were furnished with four pair of muscles ; and another pair ran over them, to which they performed the office of a trochlea, or pulley. The first pair of muscles (i.e. which first came to be dissected, on the pronation of the animal, and from its figure I call triangularis,) arise fleshy from the whole length of the internal side of these bones, and insert their opposite tendons on each side of the rima, or aperture of the marsupium. Under part of the muscles lay another, or a second pair, flat and thin, having their origin from the upper part of the internal side of the ossa marsupialia, and inserting their opposite tendons a little above the tendons of the former muscles : the tendency or direction of the muscular fibres of this pair, in respect of the first, made a decussation. The third pair of muscles had their rise from the fore-part of the basis of these bones, where they were joined to the os pubis; and were afterwards inserted into the linera aspera of the thighbone. The fourth pair arose from the external side of these bones near the basis, and are inserted into the fore-part of the thigh-bone near the middle. The last pair of muscles arises more immediately from the marsupium or pouch itself; for spreading their muscular fibres all over this bag, as they issue from it, by joining their fibres together, they more remarkably form a solid muscle; which passing on each side over the middle of these bones, i. e. in the prone posture of dissecting the animal, they at length were inserted into the spine of the os ileum.
By considering the structure of these muscles, and what must be the effect of their action or contraction, one cannot but think the first two must serve towards the dilatation or
opening the marsupium or pouch: for these bones are a fulci. ment or basis, their articulation not admitting of a contraction inwards, or nearer to each other ; wherefore, when the first and second pair of muscles act, or contract, they must necessarily open or dilate the mouth of the marsupium or pouch. The third and fourth pair may serve to extend these bones outwards ; so that when this animal hangs by its tail, as it frequently does, the weight of the fætus in this pouch by this means will not press so much on the internal viscera. The fifth and last pair, as they may serve to dilate the capacity of the pouch itself, so likewise may serve the better to suspend its weight, when the animal is prono capite, and if it gravitates too much, they may retract it upwards, and this the easier, as passing over these bones like a pulley, their force is more augmented. The antagonist to these muscles is the sphincter marsupii
, an oval series of strong fleshy fibres, which serve to constringe and close the orifice of the pouch ; which it does so perfectly, that one would think the skin here not to be slit; nor can the orifice be observed till it is dilated with the fingers.
The pouch, or marsupium itself, was a membranous body, not very thick, though consisting of several coats, and is reducible to the class of the vesicular parts of the body; which seem to be partly muscles, partly glands, and to perform the office of both motion and secretion : for the cavity of this pouch was somewhat hairy, and at several places I could observe them matted together by a yellowish substance, which oozed out of the cutaneous glands. This liquor discharged into the pouch from the glandulous coat was strong scented, and had more of the peculiar fætor of this animal than any part besides. But after the skin, with the pouch, had been kept for some days, and was grown dry, there was so great an alteration in the smell, that what before was so disagreeable, was now become a perfect perfume, and smelled altogether like musk; though the general consent of all authors had branded it with the note of a fætid stinking animal. But the same is to be observed in the richest perfumes we have, as musk, civet, and ambergris.
This marsupium had likewise a muscular coat, besides the several other muscles bestowed on it, to give it motion. It had also a vascular coat, being plentifully irrigated by blood vessels, especially by two large branches, that came from the upper part of the thorax, and might be reckoned the mammaria, as they are styled in other animals. This pouch was fastened by several membranes to the muscles of the abdomen
and the skin, but so as to be easily separated, for the most part, with my fingers.
In this marsupium, or pouch, many writers on the natural history of this animal place the mammæ or teats ; and they tell very odd stories about it: I will only relate what they say of it, and what I at present observed, or rather did not observe. I did not find any teats here, nor even on the outward skin, as is usual in other multiparous animals. Possibly this subject never had a litter ; and for want of drawing, the teats might be less, so as to escape notice. The male also, if we may believe Piso, has such another purse under his belly, and takes his turn to carry the young, in order to ease the female. This contrivance of nature for securing the young from any danger, till they are able to shift for themselves, is perhaps not to be paralleled in any other species of animals, at least of the quadruped kind.
The first two vertebræ of the tail had only one small acute spine; but in all the other vertebræ of the tail, both at the head and tail of each vertebra, there were two spines; but those at the head of the joint the larger. In the first six vertebræ of the tail there was on each side a broad transverse process, the length of the joint ; in the other vertebræ, only at the head and tail a jetting out at the sides. The vertebræ about the middle of the tail were the longest; being there about an inch long; nearer the root of the tail, and at the end, not so long
But there is a wonderful piece of nature's mechanism in those spines or hooks, placed in a line in the middle of the under side of the vertebræ of the tail. It is true the first three vertebræ had none of these spines, nor were they necessary here, since they lay within the compass of the ossa coxendicis; but in all the other vertebræ, to the end of the tail, they were to be observed ; and as they approached the extremity of the tail, they grew less and shorter. These spines, where longest, were about one fourth of an inch, or somewhat more : they were placed just at the articulation of each joint, and in the middle from the sides, and seemed to be articulated, both to the preceding and following vertebra ; not being an entire solid bone, but rising from the verte. bræ with crura or legs, become afterwards perfectly united at the ends. By this means, these bones are rendered more firm and strong, and this hollow serves for transmitting the blood-vessels through them ; and one may here observe a stria or furrow, all the length of the vertebræ, for receiving them ; by which they are the better secured from compres