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brane from the brain, under which I have seen small veins of an admirable and incredible fineness, and as far as I was able to discern they consist of exceedingly thin filaments. I have further observed, that the said veins which thus run through the thin membrane disseminate their ramifications through the brain, after the manner as vines lying upon

the earth shoot roots into the ground; imagining the brain to be like the earth, and the veins like the roots in it.

Proceeding to the parts of the brain itself, I must still say of them that they consist of no other parts but globules; but where the brain lay spread very thin, cut through with a knife, as if they had been separated from each other, there they appeared like a very clear matter resembling oil. Continuing my observations, not only of the brains of beasts but also of fishes, and particularly of a cod-fish, and representing it very plainly to my eye, I saw that the said oleaginous matter had not been caused by the knife, but was a matter by itself, wherein the aforesaid globules lay.

Among the said globules, of which the brain partly consists, I have seen blood globules, which may plainly be discerned from the brain-globules, especially by the perfect roundness which the blood globules had. These blood globules I imagined came out of the sanguineous vessels which run through the brain, and had been cut in pieces by the knife.

I have also observed the spinal marrow of a calf, pullet, sieep, and cod-fish; which have found to consist of no other parts than those of the brain ; yet with this difference, that besides the globules in the brain, there lay in the spinal marrow a great number of shining oleaginous globules of divers sizes, some of them 50 times larger than others; and those also very soft and fluid. These spinal marrows were also furnished with exceedingly thin and manifold small veins or vessels ; and besides these very small veins, there

up and down along these spinal marrows brown filaments, thinner than the hair of the head. I perceived that each filament was not one single vessel by itself, but that each of them consisted of divers very small threads or vessels, lying by each other, between which threads there lay very clear vessels of the fineness of a single silk-worm thread.

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The Manner of hatching Chickens at Cairo. By Mr. John

GRAVES. — [1677.] The people begin in the middle of January to heat the ovens, employing every morning 100 kintars, or pounds'

weight of camel's, or of buffalo's dung, and the like quantity at night, till the middle of February. About which time the ovens are so hot, that a person can hardly endure to lay his hand on the walls. After this, they put the eggs into the ovens, to hatch the chickens, which they continue successively till the end of May.

The eggs are first put upon mats in the lower ovens which are on the ground; 7000 or 8000 eggs in number, and laid only double, one upon another. In the ovens above these lower, the fire is made in long hearths or little channels, having some depth to receive the fire, from whence the heat is conveyed into the lower ovens before mentioned. The eggs which are directly under these hearths, lie treble one upon another; the rest, as was said, only double. At night when they renew the fires in the hearths above mentioned, they then remove the eggs that were directly undermost, lying treble one upon another, in the place of those which lay on the sides only double, and these being now removed, they lay treble under the hearth, because the heat is there greater than on the sides where the eggs are only double. These eggs continue in the lower ovens fourteen days and nights; afterwards they remove them into the upper ovens, which are just over the lower. In these, there being now no more fire used, they turn all the eggs four times every day or twenty-four hours. The fire in the upper ovens, when the eggs åre placed in the lower, is thus proportioned: The first day, the greatest fire. The second, less than the first. The third, less again. The fourth, more than the third. The fifth, less. The sixth, more than the fifth. The seventh, less. The eighth, more. The ninth, without fire. The tenth, a little fire in the morning. The eleventh, they shut all the holes with flax, &c. making no more fire ; for if they should, the eggs would break. They take care, that the eggs be no hotter than the eye of a man, when they are laid upon it, can well endure. The twenty-first or twenty-second day the chickens are hatched, which the first day eat not; the second they are fetched away by women, who give them corn, &c.

When the chickens are hatched they put them into the lower ovens, which are covered with mats. Under the mats is bran, to dry the chickens; and upon the mats straw, for the chickens to stand on.

The master of the ovens has a third part of the eggs for his cost and pains, out of which he is to make good unto the owners, who have two thirds in chickens for their eggs, such as may happen to be spoiled or miscarry.

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Account of the Tin Mines in Cornwall. By Dr. CHRIS

TOPHER MERRET. - [1678.] The stones, from which tin is wrought, are sometimes found a foot or two below the surface of the earth, but most usually between two walls or rocks, and are commonly of an iron colour, of little or no affinity with the tin, and lying in a vein or load between four and eighteen inches broad. Sometimes there is a rich and fat metal; sometimes hungry and starved; sometimes nothing but a drossy substance, neither purely earth, nor stone, nor metal; but a little resembling the rejected cinders of a smith's forge; and where this is found the miners judge the metal to be ripe.

The pits are 40, 50, or sometimes 60 fathoms deep and more. The load being very rich and good, above that is about 10 fathoms from the grass ; and below that there is a large cavity, containing nothing but air, for many fathoms deep. This cavity lies between hard stony walls, about six or nine inches asunder.

Tin is usually incorporated with the stone, or is found in it. They break every individual stone; and if there be

any

blackness in the stones, of this black stuff the tin is produced. Sometimes it is as it were mixed with a small gravelly earth; sometimes white, but for the most part red. From this earth it is easily separated by bare washing; but from the stone not without much stamping. This gravelly tin they distinguish from that which is gathered from the stones, calling it pryan tin, and is but about half the richness of the other. They have another sort of ore, called mundic ore. Being mixed together, the mundic may be easily known by its glittering, yet deep brownness. The mundic is said to nourish the tin ; and yet they say where much mundic is found there is little or no tin; and where there is little or none of that, much and good tin is found. Certain it is, if there be any mundic left in melting the tin, it does it much prejudice, making it less ductile. For tin without it will easily bend any way; but mixed with it, becomes very brittle, and will crack and break.

This mundic seems to be a kind of sulphur. Fire only separates it from the tin, and evaporates it into smoke. Little sprigs or boughs being set in the chimney, the smoke gathers upon them into a substance, which they call poison, and think it is a kind of arsenic; which being put into water, easily dissolves, and produces very good vitriol. The water in which it is dissolved soon changes small iron rods put into it. When they burn it to separate it from the tin, it sends forth a very loathsome and dangerous stench.

Besides the fore-mentioned stones, &c. found in tin mines, and incorporated with the tin; there occurs a spar, mixed also with this metal, as it is commonly with lead and copper, This appears frequently of a shiny.whitish substance; and casts a white froth on the water in washing it. When first taken out of the earth it is soft and fattish, but soon after grows somewhat hard. The miners call it white spar.

The Cornish diamonds, so called, lie intermixed with the ore, and sometimes on heaps : some of them large enough to have a coat of arms engraven on them; and are hard enough to cut glass. Some of them are of a transparent red, and have the lustre of a deep ruby. These diamonds seem to me to be but a finer, purer, and harder sort of spar ; for they are both found together, as on St. Vincent's rocks near Bristol.

The working of the ore is performed in this manner : The stones, first previously beaten, are brought to the stampingmill. They are so disposed, as that by degrees they are washed into a latten-box with holes, into which the stampers fall: by which means they are beaten pretty small, and by the water continually passing through the box, the ore through its weight, falls close by the mill, and the parts not metalline, which they call causalty, are washed away by the water; and thus the first separation is made. They then take that which falls close by the mill, and so dispose it in the said mill, that the water may once more drive it, to make a better separation of the causalty. Next they dry it in a furnace on iron plates, and then grind it very fine in a crazing-mill, with stones common in the hills of that country. After this they rewash it as before, and then dry it a little, and so carry it to the furnace, called a blowing-house, and there melt and cast it.

Of Red Snow seen at Genoa. By Sig. SAROTTI. [1678.]

ON St. Joseph's day, on the mountains called Le Langhe, there fell on the white snow, that lay there before, a great quantity of red, or if you please, of bloody snow. From which, being squeezed, there came a water of the same colour.

Observations in Congo. By MICHAEL ANGELO DE GUATTINI.

[1678.] In the kingdom of Congo there are serpents 25 feet long, which will swallow at once a whole sheep. The manner of . taking them is thus : when they lie to digest what they have eaten, they stretch themselves out in the sun, which the blacks seeing kill them. And having cut off their head and tail, and embowelled them, they eat them; and usually find them as fat as hogs. There are here a great number of ants, and so large, that the author reports that being one day sick in his bed he was forced to order himself to be carried out of his room for fear of being devoured by them. As it often happens to those of Angola, where may be seen in the morning the skeletons of cows devoured by these animals in one night.

On the Structure of Teeth and other Bones, also of Hair.

Ву Mr. AŇTony LEUWENHOEK. — [1678.] HAVING some time since applied a glass, esteemed a good one, to observe the structure of the teeth and other bones, they then seemed to consist of globules. But since then, having drawn out one of my teeth, and for further observation applied better glasses than the former, it has plainly appeared that the whole tooth was made

up
of

very small, straight, and transparent pipes. 600 or 700 of these pipes put together exceed not the thickness of one hair of a man's beard. In the teeth of a cow, the same pipes appear somewhat larger, and in those of a haddock somewhat less. I have also observed part of the shin-bone of a calf, six or eight weeks old, in which the pipes are less straight than in a tooth ; and sometimes there seemed to be several lesser pipes joining together, so as to constitute a larger one.

The grain of ivory appears like the fibres or threads of a muscle, running in parcels, decussatim, and under and over each other reciprocally, and so making up one piece of platted work.

I have formerly, also, with others, examined the structure of hair ; and we agreed that it consisted wholly of globules. But not being satisfied without further enquiry, I took the hair of my beard after it had been shaved the first, second, third, and fourth days, and observed, that the little particles which we saw through the common microscopes, which yet were very good, and which appeared round, were indeed irregular, and lay very closely pressed one upon another. Of

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