Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/973

 • LAP

it was a ftone much ufed among the Greeks in their fepul- tures, and is recorded to have always perfectly confirmed the flefh of human bodies, buried in it, in forty days. This property it was much famed for, and all the antient natura- liffs mention it. There was another very fingular quality alfo in it, but whether in all, or only in fome peculiar pieces of it, is not known; that is, its turning into none any thing that was put into Veffels made of it. This is recorded only by Mutianus and Theophraftus, except that Pliny had co- pied it from thefe authors, and fome of the later writers on thefe fubjects from him. The account Mutianus gives of it is, that it converted into ftone the fhoes of perfons bu- ried in it, as alio the utenfils which it was, in fome places, cuftomary to bury with the dead, particularly thofe which the perfon, while living, moft delighted in. The utenfils this author mentions, are fuch as mull have been made of Very different materials ; and hence it appears that this jftone had a power of confuming only flefh, but that its pe- trifying quality extended to fubftances of very different kinds. "Whether ever it really poflefled this laft quality has been much doubted, and many, from the feeming improbability of it, have been afraid to record it. What has much en- couraged the general dilbelief of it, is, Mutianus's account of its taking place on fubftances of very different kinds and textures; but this is no real objection, and the whole ac- count has probably truth in it. Petrifactions in thofe early days riiight not be diftinguifhed from incruftat'ions of fparry and flony matter on the furfaccs of bodies only, as we find they are not with the generality of the world even to this day ; the incruftat'ions of fpar on modes and other fubftances in fome of our fpririgs, being at this time called by many petrified mofs, &c. and incruftations, like thefe, might ea- fily be formed on fubftances enclofed ih veflels made of this ftone, by water paffing through its pores, diflodging from the common mafs of the ftone, and carrying with it parti- cles of fuch fpar as it contained ; and afterwards falling in repeated drops on whatever lay in its way, it might again depofit them on fuch fubftances, in form of incruftations. By this means, things made of ever fo different matter, which happened to be enclofed, and in the way of the paflage of the water, would be equally encrufted with, and in ap- pearance turned into ftone, without regard to the different configuration of their pores and parts. The place from whence the antients tell us they had this ftone was Alios, a city in Lyua, in the neighbourhood of Which it was dug ; and De Koot informs us, that in that country, and in fome parts of the Eaft, there are alfo ftones of this kind, which if tied to the bodies of living perfons, would in the fame manner confume their flefh. Hifr$ Notes on Theophraftus, p. 14.

Lapis atramentarius, the copper Jlone. See Pyrites.

Lapis Bononienjts, the Boloni an Jione. The art of preparing this ftone fo as to make it fhine in the dark, has been fuppofed by many to be long loft in its utmoft perfection, and indeed that there were but few people who were ever truly pof-

- fcfl'ed of it. The whole is, however, defcribed at large in Hook's Philofophical Collections, by Sir Marc Antonio Cellio, and in a book of the fame author, publifhed at Rome in 1680, exprefsly on that fubject.

The principal places near Bolonia, where this Jione is found, are, 1, At Pradalbino. 2. In a fmall brook near the village Roncania, where it is found among a large quantity of a white ftone like fal armoniac, and an cruginary ftone, which yields a vitriolic efflorefcence : thefe are probably a fibrofe talc, and a pyrites. And 3. At Monte Patemo, which is the moft noted place of all for thefe Jioms ; and thofe found

- here are faid to fucceed beft in the operation. The ground where it is found is barren, and abounds with fmall globular gold coloured pyrita?. The Jione is found moft ealily after


 * rain ; when the earth being warned away, the feveral manes

of it appear as bright as burnifhed filver, or with the glit- tering of talc, refcmbling the glofs of a looki ig glafs. II Tosforo de Marc. Anton, Cellio,

The Jione is of no certain figure, but is fometimes round, Tometimes oblong and cylindric, fometimes lenticular; the laft kind ufually proves the beft of all, as being more film- ing and transparent. They are ufually as big as an orange, and fometimes arc found of five pound weight, and are very light, confidering their bulk. They are of various co- lours ; fome are afh coloured, fome of a fky blue, fome of a ferrugmeous colour, others yellow, others grevifh white, and fome almoft perfectly white. The beft for ufe are the iky coloured and the white. When this jione is prepared, it affords an efflorefcence, in which lies its principal virtue of receiving light; which it does, either from the fun, the moon, the common day light, or a flame, but in different degrees. When carried into the dark, it appears exactly

. like a burning coal, and the light it gives is fufKcient to read by, if the letters be placed near the Jione. It does not re- tain its light long, but requires often renewing; and when Well prepared, its virtues will laft five or fix years, but fel- dom longer. The way of feeing it to the greateft advan- tage, is after the eye has been kept for fome time in a dark Suppl. Vol. I,

LAP

\ room, and the ftone is brought in there immediately from be- ing held in the fun.

The beft method of preparing it is this: make a cylindric furnace of iron or copper plates, feven inches in diameter, and as many in height. Line the infide of it with a itrong lute, fo that the infide may be fix inches wide in the clear hollow : at the top of this there are to be made four notches of 2 \ inches deep, and 1 \ inch wide; to this make fuch a cylindrical partof the fame diameter, but a little higher, and make at the bot- tom two afh-holcs, or air-holes, big enough to put in one's hand. Line this, as the other, with good lute, and give it a bottom of lute, that it may the more ftrongly reflect the heat, and make a cover for the top, lining it in the fame manner with lute : into this furnace put an iron wire grate near the bottom, to fuftain the coals, and freely admit the air. On this grate lay fome pieces of lighted charcoal, and on thefe put others not lighted, all broken to the fize of a walnut, or thereabouts. Some of the ftones muft be powdered, and thofe which are to be calcined muft be dipped in ftrong aqua vita?, and while wet rolled in this powder. Thefe ftones, thus covered, muft be laid upon the bed of charcoal clofe to one another, and another bed of charcoal, in the like fmall pieces, muft be laid over them up to the top of the furnace. The cover of the furnace is then to be put on, and the fire lighted. When the charcoal is all burnt away, and the whole is cold, take out the ftones, and taking out the cruft from them, wrap them up in filk, and keep them in a clofe box for life. The cruft which is taken off from the ftones is to be pre- ferved ; it Alines as Well as the ftone, and is to be beat to powder, and rubbed over z\\y thing that is to be made to fhine ; the thing being firft daubed over with the white of an egg : this will make it flick oh, and the whole will fhine like the ftone.

The furnace here defcribed is not abfolutely necefTary to the Tuccefs of the operation ; but it is convenient to know the quantity of charcoal necefTary to give the fhining quality to the ftone, fince an over heat deftroys it, and too fmall a

■ degree is not fufficient to raife it.

Lapis cauda cancri, in natural hiftory, a name given by Gefner, and fome other writers, to the foflile fliells, fince called tubuli marini concamerati, and by fome polytbahmiii and

. ortho-ceratiiee. Seethe article Tueul us eoncameratus.

CoHcus Lapis. See the article CoiAC-Jione.

Lapis csrneUs% 'born Jione, a name given by many of the Ger- man authors to flint, which fome of them have alfo very improperly called pyrites, or the fire ftone, becaufe it is ufed to ftrike fire with.

Burner, in his corallograpbia fubterranea, has a remarkable fyftem in regard to flint. He is of opinion, that all flints are foflile corals. He fets out with a juft principle, viz. that of thofe things found under ground exactly refenibKng animals, vegetables, or parts of them, which may be now found recent, living, or growing, not one is of true mineral origin ; but that they are in reality ftones, formed in or upon the very fliells they reprefent. As it is very eafy to find corals that refemble our common flints, and as many of the branched, and oddly figured flints, found in our chalk pits, have fomething of the external fhape of fome of the (pe- des of white corals ; he concludes, that they were ori- ginally fuch, and have been only altered into the ftare and fubftance we find them in, by time. The trunk and branches of the white corals may be found very nicely rcprcfented in fome of the oblong ramofe flints found in ftrata of chalk ; and in thefe, as well as ih thofe now found in the lea, fome of the branches are intire, and fome are truncated, The inner fubftance of the corals, and that of thefe flints, is fmooth, hard, and uniform; and the flints have a white thin cruft on their outfide as the corals have. Thefe are the " principal foundations on which he has built his new opinion. But it is to be obferved, that the refemhlances of flints and corals are but very flight and fuperficial, and we have no proof from their internal ftructure of their being at all alike. [* Vid. Burner, Corallog. Subter.]

Lapis dfainus, a fpecies of jafper, fo called from its imagi- nary virtues, as a diuretic and expeller of poifons. It is found in the fliores of the Ganges and other parts of the Eaft Indies.

The Turks are extremely fond of it in their curious works, particularly for the handles of their fiibres.

Lapis Hycnius. See Hyenius Lapis.

Lapis Hybemkus, a foflile of the flate kind, fo ftrongly im- pregnated with alum as to deferve the name of an alum ore ; it often contains alfoa portion of vitriol, and is found in many parts of Ireland, as well as in feveral of our own counties.

It is given in powder as a ftyptic in all kinds of hae- morrhages with fuccefs ; but, as it owes all its virtues to alum, it might be full as prudent to give this fait in its ftead.

Lapis Iflebeianus. See Islebeianus Lapis,

Lapis Judahus, See Judaicus lapis.

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