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An Account of the Strata of Bogs, and of Horns found under
Ground in Ireland. By Mr. JAMES KELLY. - [1726.]
MARL is found only in the bottoms of low bogs, where it is searched for with augres, and found at the depth of seven, eight, or nine feet; this in many places occasions great expence in draining off the water. For the first three feet they meet with a fuzzy sort of earth, called moss, proper to make turf for fuel; then a stratum of gravel about half a foot; under which, for about three feet more, is a more kindly moss, that would make a more excellent fuel; this is altogether mixed with timber, but so rotten, that the spade cuts it as easily as the earth ; under this, for the depth of three inches, are leaves, mostly of oak, that appear fair to the eye, but will not bear a touch. This stratum is sometimes interrupted with heaps of seed, that seem to be broom or furze seed; and in one place there appeared to be gooseberries and currants ; in other places in the same stratum they find seaweed, and other things as odd to be at that depth ; under this appears a stratum of blue clay, of half a foot thick, fully mixed with shells ; this is esteemed good marl, and thrown up as such; then appears the right marl, commonly two, three, or four feet deep, and in some places much deeper, which looks like buried lime, or the lime that tanners throw out of their lime-pits, only that it is much mixed with shells, being the small periwinkles, called fresh-water wilks ; though there are among them abundance of round red periwinkles; such as are often thrown out on the sea-shore.
Among this marl, and often at the bottom of it, are found very great horns, which, for want of another name, are called elk-horns: where they join the head, they are thick and round; and at that joining there grows out a branch of about a foot long, that seems to have hung just over the beast's eyes ;
round above this for about a foot or more ; then spreads broad, which ends in branches, long and round, turning with a small bend. They have also found shanks and other bones of these beasts in the same place.
On the Controversy among Mathematicians, concerning the
Proportion of Velocity and Force in Bodies in Motion. By the Rev. Dr. SAMUEL CLARKE. [1728.]
It is contended, that the force of any body in motion is proportional not to its velocity, but to the square of its velocity. The absurdity of which notion I shall first make appear,
and then show what it is that has led these gentlemen into
In the nature of things, it is evident, that every effect must necessarily be proportionate to the cause of that effect; that is, to the action of the cause, or the power exerted at the time when the effect is produced. To suppose any effect proportional to the square or cube of its cause, is to suppose that an effect arises partly from its cause, and partly from nothing.
In a body in motion, there may be considered, distinctly, the quantity of the matter, and the velocity of the motion. The force arising from the quantity of the matter, as its cause, must necessarily be proportional to the quantity of the matter ; and the force arising from the velocity of the motion, as its cause, must necessarily be proportional to the velocity of the motion. The whole force, therefore, arising from these two causes must necessarily be proportional to these two causes taken together. And, therefore, in bodies of equal size and density, or in one and the same body, the quantity of matter continuing always the same, the force must necessarily be always proportional to the velocity of the motion. If the force were as the square of the velocity, all that part of the force, which was above the proportion of the velocity, would arise out of nothing.
Whenever any effect whatever is in a duplicate proportion, or as the square of any cause, it is always either because there are two causes acting at the same time, or that one and the same cause continues to act for a double quantity of time.
The resistance made to a body moving in any fluid medium is in a duplicate proportion to the velocity of its motion; because, in proportion to its velocity, it is resisted by a greater number of particles in the same time; and again, in proportion to its velocity, it is resisted by the same particles singly with a greater force, as being to be moved out of their places with greater velocity.
What I have thus demonstrated concerning any force, considered as the cause producing an effect, and concerning the time, during which the force operates, is on all hands acknowledged to be true concerning velocity. And, therefore, velocity and force, in this case, are one and the same thing. So that to affirm force to be as the square of the velocity, is to affirm that the force is equal to the square of itself.
Observations made by a young Gentleman, who was born
blind, or lost his Sight so early, that he had no Remembrance of ever having seen, and was couched between 13 and 14 Years of Age. By Mr. WILLIAM CHEsselden, F.R. S.
This young gentleman knew colours asunder in a good light, yet when he saw them after he was couched, the faint ideas he had of them before were not sufficient for him to know them by afterwards ; and therefore he did not think them the same, which he had before known by those names. Now scarlet he thought the most beautiful of all colours, and of others the most gay were the most pleasing ; whereas the first time he saw black, it gave him great uneasiness, yet after a little time he was reconciled to it; but some months after, seeing by accident a negro woman, he was struck with great horror at the sight.
When he first saw, he was so far from making any judgment about distances, that he thought all objects whatever touched his eyes, as he expressed it, as what he felt did his skin ; and thought no objects so agreeable as those which were smooth and regular, though he could form no judgment of their shape, or guess what it was in any object that was pleasing to him.
He knew not the shape of any thing, nor any one thing from another, however different in shape or magnitude ; but on being told what things were, whose form he before knew from feeling, he would carefully observe, that he might know them again ; but having too many objects to learn at once, he forgot many of them; and, as he said, at first he learned to know, and again forgot a thousand things in a day.
One particular only, though it may appear trifling, Mr. C. relates : having often forgot which was the cat, and which the dog, he was ashamed to ask; but catching the cat, which he knew by feeling, he was observed to look at her steadfastly, and then setting her down, said, So, puss ! I shall know you
another time. He was very much surprised, that those things which he had liked best did not appear most agreeable to his eyes, expecting those persons would appear most beautiful that he loved most, and such things to be most agreeable to his sight that were so to his taste. They thought he soon knew what pictures represented, which were showed to him, but they found afterwards they were mistaken: for about two months after he was couched, he discovered, at once, they represented solid bodies ; when to that time he considered them only as party-coloured planes, or surfaces diversified with va. riety of paint; but even then he was no less surprised, expecting the pictures would feel like the things they represented, and was amazed when he found those parts, which by their light and shadow appeared now round and uneven, felt only flat like the rest; and asked which was the lying sense, feeling, or seeing ?
Being shown his father's picture in a locket at his mother's watch, and told what it was, he acknowledged a likeness, but was vastly surprised; asking, how it could be that a large face could be expressed in so little room, saying, it should have seemed as impossible to him as to put a bushel of any thing into a pint.
At first, he could bear but very little sight, and the things he saw he thought extremely large ; but on seeing things larger, those first seen he conceived less, never being able to -imagine any lines beyond the bounds he saw; the room he was in he said he knew to be but part of the house, yet he could not conceive that the whole house could look larger. Before
vas couched, he expected little advantage from seeing, worth undergoing an operation for, except reading and writing; for he said he thought he could have no more pleasure in walking abroad than he had in the garden, which he could do safely and readily. And even blindness, he observed, had this advantage, that he could go any where in the dark much better than those who can see; and after he had seen, he did not soon lose this quality, nor desire a light to go about the house in the night.
He said, every new object was a new delight, and the pleasure was so great, that he wanted ways to express it; but his gratitude to his operator he could not conceal, never seeing him for some time without tears of joy in his eyes,
and other marks of affection ; and if he did not happen to come at any time when he was expected, he would be so grieved, that he could not forbear crying at his disappointment.
A year after first seeing, being carried upon Epsom Downs, and observing a large prospect, he was exceedingly delighted with it, and called it a new kind of seeing. And now being lately couched of his other eye, he says, that objects at first appeared large to this eye, but not so large as they did at first to the other; and looking on the same object with both eyes, he thought it looked about twice as large as with the first couched eye only, but not double, that they could any ways discover.
An Account of Elephants' and Mammoths' Teeth and Bones, found under Ground. By Sir Hans Sloane.- - [1728.]
It is observable, that among the vast variety of extraneous substances, lodged and found in several layers of the earth, at considerable
depths, where it is impossible that they should have been bred, there are not so many productions of the earth as of the sea. And again, among those which must have originally belonged to the earth, there are many more remains of vegetables than of land animals.
It appears, however, by the histories of past times, and the accounts of many, both ancient and modern authors, that bones, teeth, and sometimes almost whole skeletons of men and animals, have been dug up, in all ages of which we have histories, and almost in all parts of the world, of which the most remarkable for their unusual size have been also the most noticed. Thus, for instance, in Ireland there have been found the horns, bones, and almost entire skeletons of a very large sort of deer, which is commonly believed to have been the moose-deer, an animal of an uncommon size, some of which kind are thought to be still living in some remote and
unfrequented parts of the continent of America.
The tusk of an elephant was taken up, 12 feet deep, from among sand, or loam, in digging for gravel at the end of Gray's Inn Lane.
An extraordinary elephant's tooth, one of those which grow out of the upper jaw, and which for their magnitude and length have by some writers been accounted horns, was lately taken out of the earth by digging in Bowdon-parva Field in Northamptonshire. Even the native colour of it has been in a great measure preserved; but it is become brittle with lying in the earth; and was broken into three or four pieces transversely by the diggers in taking it up. One of them is somewhat above a yard, the other is two feet in length; but the whole tooth must needs have been at least six feet long; the thickest part of the larger piece is 16 inches round. The tooth lay buried above five feet deep in the earth. The strata, from the surface, downwards to the place where the tooth was lodged, were as follows: 1. The soil 13 or 14 inches. 2. Loam, a foot and a half. 3. Large pebbles, with a small mixture of earth among them, two feet and a half. 4. Blue clay: In the upper part of this stratum the tooth was found.
The tusk of an elephant, remarkable for its large size, and for its being so very entire, was found under ground in Siberia. The like tusks, and other bones of the elephant, are