Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/46

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not bed at about four inches afunder, watering and fhading them till they have taken root. They muft afterwards have as much air as the feafon will allow, and in May they muft be tranfplanted into a warm border, fetting them at two foot diftance every way. About the middle of June the fruit wil! appear, and if the weather be dry at this time, they muft be often watered, which will make the fruit grow large. ^ The fruit ripens in the end of July. Miller 7 *, Gardener's Dift. MELOPEPO, in botany, the name of a genus of plants, of a middle nature, as their name exprefles, between the melon and the pompion. The characters which diftinguifh this ge- nus from the others of the like kind, are, that the fruit is roundifh, ftriated, angular, and ufually deeply divided into five parts. The feeds are flat, and fixed to a fpongy pla- centa.

The fpecies of this genus, enumerated by Mr. Tournefort, are thefe; i. The flatted or comprefled Mehpepo. 2. The great white-fruited Mclopepo. 3. The yellow rough-fruited Mehpepo. 4. The broad deprefled Mclopepo. 5. The ci- tron-fhaped Melopepo. 6. The conic Melopepo. 7. The Mehpepo with a doubly turbinated fruit. 8. The yellow thin-fkinned Melopepo. 9. The clypeated, or fhield Melo- pepo. 10. The verrucofe or warted Mehpepo. ir. The tuberofe warted Melopepo. 12. The lightly Itriated yellow warty Melopepo, with rough leaves. 13. The white lightly itriated warty Mehpepo, with rough leaves. 14. The warty Mehpepo, with a white fruit and white feeds. MELOTIS, a word ufed by the chirurgical writers to exprefs a fmall probe, properly one intended to be ufed only to the ear. MELT {CycL}— Melt of Fijlm. In the Melt of a living cod-fifh there are fuch incredible numbers of thofe fmall ani- malcules found in the male feed of all animals, that in a drop of the juice of it, no more in quantity than a fmall grain of land, there are contained more than ten thoufand of them ; and, confidering how many fuch quantities there are in the whole Melt of one fuch fifh, it is not exceeding the bounds of truth to affirm, that there are more animals in one Melt of it, than there are living men at one time upon the whole face of the earth. However ftrange and romantic fuch a con- jecture may appear at firft fight, a ferious confideration, and calculation, will make it appear very plain. An hundred fuch grains of fand as are here mentioned, will make about an inch in length ; therefore in a cubic inch there will be a mil- lion of fuch fands.

The Melt of one of thefe fifties is frequently about the quan- tity of fifteen cubic inches, it muft therefore contain fifteen millions of quantities as big as one of thefe fands ; and if there be ten thoufand animals in each of thofe quantities, there muft be, in the whole, a hundred and fifty thoufand millions : Which is a number vaftly exceeding the number of mankind, even tho' we were to fuppofe the whole earth as populous as Holland. See Philofophical Collections, p. 4. MELTING (CycL)— Melting Cone, in affaying, is a fmall veftel made of copper or brafs, of a conic figure, and of a nicely polifhed furface within. Its ufe is to receive melted jnetals, and ferve for their precipitation, which is effected, when two bodies melted together, and yet not mixing per- fe6tly with one another in the fufion, feparate in the cooling into two ftrata, on account of their different fpecific gravity. This precipitation might be made in the fame veflel in which the fufion is performed ; but then the melting-pot or crucible muft be broken every time to get it out, whereas the conic ihape, and polifhed furface of this veflel, makes it eafily got out without violence. The fhape of this veflel is alfo of an- other ufe in the operation ; for by means of it, the heavy matter fubfiding to a point, is formed into a perfect and fepa- rate regulus, even where the whole quantity, as is very fre- quently the cafe, has been but very fmall. When the quantity of the melted matter is great, it is com- mon to ufe, inftead of this cone, a large brals or iron mortar, or any other conveniently fhaped brafs or iron veflel. It is ncceflary, when the cone is of brafs, to be cautious that it be not made too hot ; for the brittlenefs of that metal, when hot, makes it eafily break, on the ftriking with any force on that occaflon, to make the melted mafs fall out. Thefe, and all other moulds for the receiving melted metals, muft always be well heated before the mafs is poured into them, left they fhould have contracted a moifture from the air, or have been wetted by accident; in which cafe the melted me- tal will be thrown out of them with great violence and danger. They ought alfo to be fmeared over with tallow on their in- fide, that the regulus may be the more eafily taken out of them, and the furface of the mould not corroded by the melted mafs poured in.

If a very large quantity of a metal is, however, to be received into them, and especially if any thing fulphureous have place among it, this caution of tallowing the moulds does not prove fufficient ; for the large quantity of the mafs makes it conti- nue hot fo long, that this becomes but a flight defence to the furface of the mould. In this cafe the aflayer has recourfe to a lute, reduced to a thin pap with water, which being ap- plied in form of a very thin cruft, all over the infide of the cone,- or mould,, foon dries- up indeed, but always preferves

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the fides of the veftel from the corrofion of the mafs. And this caution is found neceflary, even when pure copper is melted alone, without any mixture of fulphur. See Tab. of Chemiftry, N°. 31. Cramer, Art. Aft. p. 72.

MEM/ECYLUM^ in botany, a name by which fome authors have called the arbutus, or ftrawbeiry -tree, a fhrub prefaced in the o-ardens of the curious. Ger. £mac. Ind. 2.

MEMAfCULA, in the materia medka of the anrients, a name given to a fruit, ordered in fome competitions as an aftrin- gent and a cooler. When the Greek writers ufe this word; their Latin tranflators ufually render it by the word unedo. Pliny fays, that unech is the name of the fruit of the arbuha y or ftrawberry-tree ; but we find the earlieft Latin writers do not countenance this. Varro calls the fruit of the arbutus by the name arbutus, as he does the fruit of the mulberry or morus, by the name morus. And it feems to have been con- trary to the general cuftom of the times to have impofed a name upon a fruit, different from that of the tree which bore it. Some of the commentators fay that the Memaicula, or Unedo was no other than the common wood-ftrawberry. And iEgineta in one place fays, that the fruit of the camarus, that is, of the arbutus, was called Memaicula ; but in another place he gives a much belter explication of the word, faying, that fome of the Greeks ufed it as the name of the fruit of the cotims mas, or male cornel-tree. Seethe article Cornus.

MEMBRANE {CycL) — Mr. Lewenhoek has been at the pains of examining, with great nicety, the fine Membranes which enclofe the fafciculi or fmall bundles of fibres of which a mufcle is compofed. Between thefe fafcun the Membrane is of a confiderable thicknef; ; but it divides itfelf every way into very fine and fmall branches. This Membrane is evidently compofed of a number of fmall veflels, and thefe may be di- ftinguifhed not only in its thick parts, but even where it is ever fo fmall and fine, fo far as the microfcope can trace it ; but this is not fo far as might be wiflied ; for the Membrane ftill divides itfelf in its progrefs into more and more ramifica- tions, and where it envelopes only a fingle fibre, is not to be diftinguifhed with any degree of precifion, even with the beft microfcopes. The fmall vefiels extended through this Mem- brane, are doubtlefs intended to convey nourifhment to it 5 but it is very certain, that the globules of blood can never pafs into fuch fmall canals. Phil. Tranf. N°. 122. p. 140.

Adipofe Membrane, Membrana Adipofa. It was the opi- nion of Boerhaave that the feat cf the lues venerea, or pox, was in the Membrana Adipofa. There are many feeraing difficulties which have prevented the generality of the learned world from giving into this ; but there have been fevcral par- ticular cafes, the fymptoms of which feem to prove it really to be fo.

Of thefe Dr. Huxam gives one, which alone may feem fuf- ficient to prove the reality of it. This is of a gentleman of about 27 years of age, and of a hot bilious conftitution, who fome years before his death had got a genorrhcea, and before that was well cured, a fecond, and after that a third j and after all thefe, had frequent impure converfations with the negro women in the Weft Indies, who probably had that worft fpecies of pox, the yaws. He had, after this, a ter- rible itching under his fkin, and a terrible ftinking breath, and fpit corrupt matter, but had no running ulcer, bubo, node, or other of the common fymptoms of a confirmed pox; but after repeating his rafh conduct with fome women in England, he had a Gonorrhoea of which he could not get cured ; but a bubo appeared in the groin, and verrucofe fwellings about the anus.

One of thefe breaking difcharged a great quantity of matter, and after that others appeared, the bubo would not fuppurate, and fcabs appeared in feveral parts of his body. He was fu- migated with cinnabar, and a falivation propofed ; but after taking, at times, five drams of calomel, he had not the leaft forenefs of the gums, though that medicine had not purged nor vomited him. At length turbith. vomits, and large do- fes of mercurials, to which he had been much accuftomed be- fore, brought on a forenefs of the mouth ; but the fpitting was tough, and did not amount to a pint a day. During this courfe the fcaly eruptions encreafed, and he was at length. covered with them all over, and his limbs fwelled, and even burft in many places, the fiffures discharging a ftinking icho- rous matter.

Hot baths and mercurial ointments were ufed on this, but the difeafe ftill encreafed under thefe means ; the fcales grew fo> ftiff, that he could not move his limbs, and ulcers appeared in many parts, particularly a large tumour on each breaft, which difcharged vaft quantities of an oily ftinking matter. It was obfervable, that where thefe tumours and ulcers appeared, they only ran under the fkin, being entirely feared in and feeding on the Membrana Adipofa, fo that the mufclcs and tendons underneath appeared as fair and florid as in the molt healthy conftitution.

It was now plain, that mercury could do nothing toward a cure in any form, and the old method of fweating was at- tempted with warm baths, to loofen the fcales ; by this means they came off apace in the manner of thofe of the con- fluent fmall pox, but larger, fome of thefe being four or five inches over. In a week's time, the coat of mail was cleared

off,