Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/64

 M I N

fcrent ways. The fire calcines ftones, and they then eafily become fhattered to pieces, and give way to tools that would not touch them before ; but in this cafe, befide the expence of wood, the hindrance of the labourers is an article to be confidered, for the rocks are made fo hot all about the place where the fire has been, that the people cannot get to work again of a day or two, and then the effect of fire reaches but a little way in the rock.

Gunpowder makes its way much farther, and at the fame time is much cheaper and does not delay the work, but the labourers may go on immediately afterwards. There have been many ways contrived of ufing this, but one of the fimpleit and belt, feems that delivered by Mr. Beaumont, in the fhi- lofophical Tranfactions. For this there are only three fimplc inftruments required, a boricr, a gun, and thequinet or wedge. Thefe are the names the Miners on Mendip hills give the inftruments. The boricr is an iron inftrument, fteeled at the end ; it is two foot two inches long, and is fomewhat thicker at the fteel'd end than in any other part : The ufe of this is to make the hole in the rock deep enough to receive the powder. The gun is about fix inches long, and an inch and quarter in diameter j and has a hole drilled through it, to re- ceive the priming. The quinet is a wedge of iron of about fix inches long, and fo fhaped that its flat part on one fide joins with a flat part in the gun made to receive it, and by that means the gun is faftned very firmly in its place. Philofoph. Tranf. N°. 16;?. p. 854.

The manner of uling thefe inftruments, is this : One man holds the borier on the rock, turning it round while another forces its point in by blows of a large hammer on the other end. When the hole is made fomewhat deeper than the length of the gun, they dry it with a rag, and then put into it two or three ounces of powder ; over this they lay a paper, and then they put the gun into the hole, and falten it in by ■driving in the quinet or wedge againll its flat part. When the powder and gun are thus fixed, they pafs down a wire through the hole drilled in the gun, and with this they pierce a hole through the paper which covers the powder j they then prime the gun, and lay a train With a lighted match j but all go out of the Mine before the gunpowder takes fire, and as foon as it has gone off they go down to work again, finding the rock fplit and the inftruments unhurt. The paper in this cafe is put over the powder only that the tools may be fafely employed in driving down the gun and the quinet, becaule were not the powder covered it might do mifchief to the workmen by going off by fome (park caufed by ftriking either againit thofe inftruments or againft the rock itfelf. MINIUM, [Cycl.) in the natural hiftory of the antients, a name given to what we now call Cinnabar. A native mineral of a ihinining red colour, out of which quickfilver was extracted. This native mineral becoming much in ufe, was foon adulte- rated, and that commonly with lead ore calcined to a rednefs; and hence, after the two words Minium and Cinnabar had been long ufed in common, the cinnabar became retained only to the native mineral, and the Minium to that adulterated with lead- ore, or to the red adulterating matter alone, which is the fenfe in which it is ftill ufed.

The word Cinnabar however, by which they at laft diftin- guifhed it, among the oldeft writers on medicine, was ufed as the name of a very different fubftance, a vegetable juice of a ftrong red colour, called by us dragon's blood, and among them long believed to be the dry'd blood of dragons ; and when the antients called the mineral body here defcribed by the fame name, they always diftinguifhed the other cinnabar, where they had occafion to name it, according to their ufual method by an adjective derived from the name of the place whence it was brought, calling it cinnabari Indicum, the Indian cinnabar.

The native cinnabar of the antients was the fame with ours at this time, and was found in the fame variety of forms. Theo- phraftus tells us, that it was hard and ftony, and that they had it from Spain and Colchis, where it was produced amono- the rocks. HUN Theophraft. p. 140. Many have fuppofed, from the name of a factitious cinnabar among the moil antient writers, that they were acquainted with our method of making the artificial cinnabar ; but this was by no means the cafe. What they called factitious cinna- bar, was, according to the fame Theophraftus, no other than a fine arenaceous fubftance of a fcarlet colour, and very bright and mining, which they had from one particular place only, which was in the country above Ephefus. This they carefully collected, and rubbed to a fine powder, in vefiels made of ftone, and afterwards wafhed it in other vefiels of brafs or of wood ; the coarfer matter they went to work upon again, rubbing and warning it as before, till by thefe repeated powderings and wafhings they feparated all the pure cinnabar, which always funk to the bottom of the vefiels, leaving the accidental foulneffes at top.

The factitious cinnabar of the antients, was therefore no other than 3. preparation of a native mineral, which contained a quantity of true cinnabar mixed among a large quantity of other matter, and the operation confuted in nothing but the feparating it from its other matter. The invention of this is attributed to one Callias, an Athenian, who belonged to the

M I N

filver mines ; and wasdifcovered, as mod other things have been, by accident. This man had got together a vait quan- tity of this fand, fuppofing from its colour and bri<ditncfs that it contained gold ; and tho' he found bimfelf miftaken in that, yet the working on it in hopes of difcovering that precious metal difcovered to him this excellent paint. See the article Cinnabar, Cycl. & Sitppl.

1 he method in which Minium is made in large quantities with us, is this: They firft burn lead in a furnace into a kind of litharge, by continually (fining it while melted with an iron rake; this they afterwards grind with two pair of ftones, which deliver it from one to another, the firft. pair grinding it coarfer, the fecond finer ; thefe are worked by means of a mill which moves fix- pair of them at once. When thus reduced to a fine powder, it is wafhed and then put into a furnace, and is burnt with a reverberatory fire for two or three days, all the while they continue ftirring it with a large iron rake, hun°- on a fwivel or iron hook ; and toward the end of the time they watch its being of the right colour. When this is do- ing, the fire mult not be carried beyond a certain degree, lelt the matter clod and run together. Raj's Englifli Words, p.

Minium, in medicine, is ufed externally ; it obtunds the a- crimony of the humors, allays inflammations, and is excel- lent in the cleanfing and healing of -old ulcers : It is ufed, on thefe occafions, in many of the plafters and ointments of the fhops.

MJNORATIO, a word ufed by the antients to exprefs a (light or moderate evacuation, only ferving to leficn the humors, not to carry them off.

MINOW, or Minim, in ichthyology, a name given by the Englifh to the fmall fifh, called by authors the phoxinus. According to the new Artedian fylrem, this is a fpecies of the cyprinus. See the articles Cyprinus, and Phoxinus.

MINT (Cycl.) — All the forts of Mint of which we have feveral propagated in gardens for medicinal ufe, are to be propagated by parting the roots in fpring, or planting cuttings in any of the fummer months, but they mult have a moid foil ; and if the weather proves dry, they will require very frequent wa- terings, after they are firft planted. They mould be planted in beds of four foot width, with walks two foot wide between them, and fhould be fet at five inches diftance. And they fpread fo faft at the roots that the beds fhould never ltand above three years before they are taken up and tranfplanted ; for the roots after this time will mat and clog together, fo as to choak one another. Miller's, Gardener's Diift. See the article Mentha.

Many people are fond of Mint fallad early in the fpring ; the way to propagate this, is to take up fome roots of Mint be- fore Chriftmas, and plant them pretty dole upon a moderate hot bed, covering them an inch deep with frefh earth ; the beds mult then be covered either with mats, or frames and glades, and in a month's time the Mint will come up and will foon be fit for ufe.

When Mint is cut for drying, it fhould be done juft when it is in flower, and muft always be done in a dry day ; for if cut in wet weather, the leaves will change black. It (hould then be ty'd in fmall bunches, and hung in a (hady place up- on lines.

If the foil be good, Mint will afford three crops every fpring ; but after July, they feldom are fo good, fo that the (hoots made after that time (hould be fuffered to remain till the end of September, to be cut for drying. After this cutting there (hould be about an inch of frefh earth fifted over them° which will make them (hoot much better the following fpring No plant grows fo vigoroufly and readily in water as° Mint; and therefore none is fo proper to try experiments in vegeta- tion upon.

It is generally fuppofed, that plants are the fame in their tafte and virtues in whatever foil they grow ; and this is true in regard to all of them, while they live and flourifh ; the greateft difference being only in degree. But plants removed into a foil in which they cannot thrive but in which they will be killed in time, are often altered in their nature, before they perilh. This is inftanced in nothing fo clearly as in experiments made on Mint, growing in glades of water. Let feveral fiioots of the plant grow in this°man- ner till very vigorous and ftrong, and then place near one of them a glafs of water in which fea-falt is diflblved, remove one of the roots from the frefh water into this, and the plant will be killed in a few days ; and its leaves, (talk, and e'very part will tafte ftrongly of fea-falt, though none could be im- bibed any other way than by this fingle root. Let another plant of Mint be fet near a bottle of ink, and one of its roots put into the ink, the whole plant will in a few days be- come black, and after that yellow, and will talte of the cop- peras.

It is lets wonderful that thefe unnatural falts (hould affect, the Mint in this manner, than that the infufion of another plant (hould do it ; yet this is evidently the cafe. Let a quantity of the feeds of wild garlic be bruifed and put into water, and let two or three of the roots of a vigorous plant of Mint growing in common water be put into this liquor, the whole plant will in a few days decay, and the whole plant being

chew'd