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was roundish, as in X Z Y; and presently, from the same rotundity, proceeded

M two little wheels, that had a swift gyration, always one and the

W same way, as in abc; these small wheels

N were as thick set with teeth as the wheel of

Fig... a watch; and when

h these animalcula had

0 for some time exerted their circular motion, they drew their wheels

P d into their body, and their body wholly into their sheaths, and then soon after thrust them out again with the aforesaid motion ; another while they remained as it were shut up in their shells; and though I observed the

R

Y same wheels in other animalcula also, yet their bodies differed from each other, and

H their sheaths were of a darkish colour, so that I could not easily perceive the animalcula; and they seemed to be composed of globules.

Pdef represent the sheath with the little worm Pdf in it: in the same figure, Og h show a sheath with half the body of the same animalcule għ protruded out of it; and in which, by reason of its exceeding smallness, the wheels could only be seen now and then, and that only when the body was extended, which would soon be compressed or shrunk up; and about the middle of the body of one of these, which I con

ceived to be the lower part of its Η

belly, there was another of the B в

same kind, but smaller, the tail of

A which seemed to be fastened to F OG

the other. I

ABCDEFGH represent one of these, about double the

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natural size, whilst it was in the water, and fastened to the root of the green weeds; A is the tail with which it fastens itself; C D E represent eight horns (though others that were smaller had but six); it is drawn as stretched out at its whole length; but when contracted, it was not the fourth part so long.

BH show an animalculum coming out of the body of the larger, which phenomenon at first I thought might be a young animalcule fastened by chance to an old one; but observing it more narrowly, I saw it was a partus, for I could now see, that although this animalcule, when I first discovered it, had only four very small horns, 16 hours after it was grown much larger, both in horns and body, and four hours after that, it forsook its mother's belly.

In the discovery of the said young animalcule, I had observed, on the other side of the body of the largest animalcule, a small round knob of seed, which, in a few hours, grew larger, and at last pointed ; and in 13 or 14 hours it became so large, that I could see two horns upon it. In 24 hours it had acquired four horns, one of which was small, the second larger, the two others very large ; and these two last were more strongly protruded and contracted than the smaller. Three hours after, this animalcule was got clear of its mother.

I endeavoured to pursue my discovery of the generation of these creatures, and in order thereto, wiped off the green weeds from the body, the better to make my observations ; when the animalcule was found not only dead, but his horns and part of the body quite wasted.

Another animalcule, that had brought forth two young ones, had her body laden with another sort of animalcula, whose shape was flat below, and round above, which I have observed in most waters; and this last sort were above a thousand times less than the others on which they crawled, and hindered their motion ; but a much larger animalcule, whose body was almost round, tormented one of the aforesaid animalcula, not only by running upon its body, but by clinging so fast to one of its horns, that whatever effort the other made to get rid of it, she could not shake it off; and at last I found she had lost one of her horns in the scuffle.

I observed in the green weeds abundance of strange animalcula, some of which feed upon the same green stuff, and to others it serves instead of skulking holes, to hide themselves from the fish, which would otherwise devour them.

Concerning a Water-spout, lately observed at Hatfield. By

the Rev. Mr. ABR. DE LA PRYME, F. R. S. - [1703.]

On the afternoon of June 21. 1702, about two o'clock, no wind stirring below, though it was somewhat great in the air, the clouds began to be much agitated and driven together; on which they became very black, and were very visibly hurried round, from whence there proceeded a most audible whirling noise, like that commonly heard in a mill. After a while a long tube or spout came down from the centre of the congregated clouds, in which was a swift spiral motion like that of a screw, when it is in motion, by which spiral nature and swift turning water ascends up into the one as well as into the other. It proceeded slowly from west to north-east, broke down a great oak-tree or two, frightened the weeders out of the field, and made others lie down flat, to avoid being whirled about and killed, as they saw had happened to several jackdaws, which were suddenly snatched up, carried out of sight, and then thrown a great way

off
among
the corn.

At length it passed over the town of Hatfield, to the great terror of the inhabitants, filling the whole air with the thatch it took off from some of the houses ; then touching on a corner of the church, it tore up several sheets of lead, and rolled them together in a strange manner ; soon after which, it dissolved and vanished, without doing any further mischief.

It is commonly said, that at sea, the water collects and bubbles foot or two high under these spouts, before they are joined: but this is a mistake, owing to the pellucidity and fineness of those tubes, which certainly touch the surface of the sea before any considerable motion can be produced in it, and that when the pipe begins to fill with water, it then be. comes opaque and visible. As for the reason of their dissolve ing of themselves, after they have drawn up a great quantity of water, I suppose it is by and through the great quantity of the water they have carried up, which must needs thicken the clouds, impede their motion, and by that means dissolve the tubes.

up a

Abstract of Letters relating to some Microscopical Observations.

The greatest of my microscopes shows a hair of the head considerably above an inch in diameter; and some eyes see it at least two inches ; but supposing it a bare inch, and that, as Mr. Hook affirms, 640 hairs' breadth makes one inch, the length and breadth of an object will by it be enlarged 640 times, the surface 409,600, and the solidity 262,144,000.

One of the first objects I tried my glasses by, was a living louse; in which I could plainly see the motion of the muscles, when he moved his legs; which are all joined in a longish dark spot in the middle of his breast, where the tendons seem all united. The like motion of muscles is also visible in the head when he moves his horns, and in the several articulations of his legs. I saw also clearly a multitude of various branchings of arteries and veins, and the pulse regularly beating in several arteries. But the most entertaining sight is the pe- . ristaltic motion of the intestines, which is continued from the stomach through all the guts to the anus. I have observed the like peristaltic motion in a flea, and in several sorts of small transparent maggots and caterpillars.

I thought a mite would also prove a good subject for the microscope; but found them not so transparent as I expected. However I plainly saw, that all the bristles on the body of one of them (which to a common single glass, and to the greatest magnifier of my three-glassed microscope, look like plain smooth hairs,) were, when viewed with a large magnifier, all spicated, or bearded like the ear on the seed-head of some grasses ;

and

every bristle on the whole body and legs, both long and short, had the same formation.

Having pulled off a handful of muscles, which stuck to a piece of a rock that was covered by the sea every tide, I found that the organs by which they fix themselves so firmly to a stone, that even a storm will not wash them off, were threads which proceeded from that part called the beard of the muscle, and which had on their extremity a flat spongy substance, that adhered only by imposition, like the suckers or wet pieces of leather which boys fasten to stones.

Some of the muscles which I brought were little more than a quarter of an inch long. I took one of these out of the shell, and exposed it to the microscope on a thin plate of Muscovy glass, and holding it to the light of a candle, I saw, in the thinner parts, a vast number of veins and arteries, and the blood circulating in them more distinctly than I ever saw it in any other animal: for I had this advantage in the observation, that the object lay always quiet, without changing place, and my plate was so thin that I could bring to it what

magnifiers I pleased, and look without disturbance as long as I pleased.

I found a small worm running among some fruit, which had a multitude of legs, and was not quite half an inch long, the body being not thicker than a hog's bristle. This insect I put alive into a small tube, and found it a perfect scolopendra, whose body was made up of 60 incisures, at every one of which was a pair of legs, one on each side, and each leg had five articulations. On his head were two horns, each of 16 joints, and under it a pair of terrible forceps, red, crooked, and pointed like the talons of a hawk; and I often saw him open and shut them, and wipe his horns through them.

I found a small black flat tick sticking on my arm, which had got its fore-part so far into the skin, that I could hardly separate it with the point of a needle, so as to preserve it entire and unhurt. I observed its snout shaped not unlike the jagged proboscis of the serra piscis: the fore-part being like the end of a broad-pointed sword, is clear and transparent, and has three teeth on each edge, below which there comes out another serrated part on each side, almost at right angles ; but this is partly hid, when viewed on the back, by a thick horn c, on the side of the head.

I afterwards examined the snouts or proboscides of dog-ticks, to see if they had the like conformation, and found their appearance as in

the fig., the snout a being so covered by the two clumsy thick horns bb, that the serrated edges could not be perceived; but separating the horns, with some difficulty, I could plainly see eight teeth, or jaggs, on each side : but the snout of a dog-tick has not the additional serrated part which is in the wood-tick. I could also perceive a tube or canal run through the snout, and see some bubbles move up and down in it.

I have found some of those animalcula in pepper-water, almost incredibly minute, which appear even to my greatest magnifiers not so large as a mite to the naked eye; and in the larger sort, I can plainly see the little feet by which they perform such brisk motions, which I never could find before. I have also discovered another sort of animalcula, which are very slender long worms, of which my pepper-water is ex

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