Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/651

 EEL

EEL

Some of the chymical writers have alfo made it e*prefs a cer- tain mixed metal, compofed of three parts, one filver, ano- ther brafs, and the third Gold.

ELIGII Morbus.) a name given by fome medical writers to a fijlula.

ELIGMA, a name given by Nicolaus, Myrepfius, and fomc other authors, to that form of medicine ufually now called a Linclus, or Lambative.

ELIQUATION, in metallurgy, is a feparation of the different parts of mixed bodies, by the different degrees of fire required to melt them. When the nature of ores, or of metallic mix- tures, is fuch, that while one part of them melts in the fire, the other more refractory and difficult of fufion remains ftill (olid ; the firft, when the mafs is placed in a mild fire, flows outofthe interfaces of the other, and is thus feparated from it. The perfection of this operation requires a different fluidity of the parts that conftitute the mafs. Lead, for inftance, melts into one mafs with copper, by a ftrong fire, whereas thefe metals cannot difiblve each other In a moderate one ; but if the mafs, compofed of both thefe, thus blended together, is afterwards expofed to a mild fire on an inclined plane, the lead alone melts, the copper becoming only brittle and fpungy, and remaining in its folid form, even when the lead has run out of it. This feparation, however, is not fo pcrfecty made, but that there ever remains fome lead in the copper, and fome fmall part of the copper is alfo carried away with the lead, wherefore it is neceffary for this experiment, that the metals are not mixed in too minute proportions, for if one thousandth part only of lead were to be mixed with copper, or the fame fmall proportion of copper with the lead, the feparation, by Eliquation, could not be effected.

It is generally neceffary alfo, in order to make this operation fucceed, to add ingredients that are capable either of deftroy- ing the force by which the different parts cohere together, or of procuring an eafier flux of the metals ; for the mixtures of the other metals will not be feparated like thofe of copper and lead, without the admixture of other fubftances. For inftance, gold, filver, and copper, melted together, and perfectly blended by that means with one another, remain in the fame ftate in any degree of fire ; to make the Eliquation of the gold and filver, therefore, out of fuch a mixture, the fame additions muft be ufed as in the operation of precipitation by fufion. Sulphur added, in this cafe, does indeed, difpofe the copper to abandon the gold and filver ; but if thefe two, as it mott commonly happens, are mixed in a very fmall quantity with a very large one of copper, then you cannot yet obtain the feparation of them ; for befide, that very fmall quantities are no more to be feparated here than in the former inftance of copper and lead, fulphur renders the copper fluid by almoft the fame degree of fire by which the filver and gold are melted ; a considerable quantity of lead muft therefore be ad- ded, in this cafe, that by the help of that addition, the gold and filver may be fufed in a gentle fire, and the copper thus feparated from them.

Precipitations by this method, and by fufion, arc both of in- finite ufe in metallurgy ; for, by means of them, minute por- tions of gold and filver may, without any great cxpence, be feparated from a large mafs of other metals, which it has not hitherto been found pomble to effect with advantage by any other method. Cramer, Art. AiT. -188.

ELIXIR {Cycl.) — Elixir. Aloes, a name given, in the late London difpenfatory, to the medicine commonly known by the name of Elixir Proprietatis, which is there alfo or- dered to be made in the following manner. Take tincture of myrrh a quart, powder of aloes, and fine faffron, of each three ounces, digeft them a due time, and then prefs off the tincture, and filter it for ufe. Pemberton's London Difp. p. 283.

Elixir Paregpricum, a name given, in the late London Dif- penfatory, to the Elixir Jjthmaticwn of Quincey ; which is there order'd to be made thus :

Take flower of benjamin, and frraincd opium, of each a dram ; camphire, two fcruples ; eflential oil of annifeeds, half a dram; redtify'd fpirit of wine, a quart. Digeft all toge- ther a proper time, and then ftrain off the fpirit. Pe?nberton'$ Lond. Difp. p. 283. ELIX1S, a name given, by fome of the old writers, to that form of medicine now called a linclus. See Linctus.

ELK (Cyd.) — The Alee, or Elk, is an animal fo differently defcribed by the antients, that it is evident they either knew very little of it, or elfe different writers have defcribed dif- ferent animals under this name. Pliny tells us, that the Elk refembles the horfe, but that the length of the neck, and Jargenefs of the ears, diftinguifh it. And Solinus, who is a copier of Pliny, afraid to give it fo large a fizc, fays, that it is like a mule. Thefe authors both add to this, what is laid alfo by many of the other Latin writers of the Elk, that its upper lip is fo large, that it cannot feed without going backwards all the time. Pliny alfo, in another place, fays this of the maclis, or machio, an animal of Scandinavia, which he defcribes by hearfay, for he acknowledges, that it never had been feen at Rome, but fays it was like the Elk. It is very poffible, that this might be the Elk under another name. Other authors compare the Elk to the goat a and

others to the flag, but they all fpeak of its long neck. Some fay it was of a fimple dufky ycllowifh colour ; and Csefar, in flis commentaries, fays, on the contrary, that it was variegated with fpots. Paufanius teils us, that it was like the flag kind, but refembled the camel in the length of its neck. It is pro- bable that the Elk of Csefar, and the Elk of Pliny and Solinus, are two different animals. See Tab. of Quadrupeds,, N°. 6. ^ *

Elk in zoology, a name by which many have called the cygnus ferus, or wild fwan. See the article Cygn us.

ELKE is mentioned, in our ftatutes, as a kind of yew to make bows of. 32 Hen. 8. cap. 9. Cowet.

ELLIPSIS, [Gyd.)~ Itnas been long known, that if a paral- lelogram, circumfcribcd about a given Ellipfe, have its fides parallel to the conjugate diameters, then will its area be of an invariable or given magnitude, and equal to the rectangle con- tained by the axes of the figure : But this is only a cafe of a more general propofition : For if, upon any diameter produced without the Ellipfe, you take two points, on each fide of the center, at equal diftances from it, and four tangents be drawn from thefe points to the Ellipfe, thofe tangents will form a parallelogram, which is always of a given or invariable magnitude, when the Ellipfe is given, if the ratio of thofe diftances to the diameter be given. And when the ratio of thofe diftances to the femi-diameter is that of the diagonal of a fquare to the fide (or of ,/ 2 to 1) the parallelogram will have its fides parallel to the conjugate diameters. Phil. Tranf. N°. 468. p. 326.

Triangles, trapezia, or polygons, of any kind, may be deter- mined, which, circumfcribed about a given Ellipfe, are al- ways of a given magnitude. For

If, upon any diameter produced without the Ellipfe, any number of points be taken, on the fame, or on different fides of the center, at diftances from it, that are each in fome gi- ven ratio to that diameter ; and from thefe points tangents be drawn to the Ellipfe, in any one certain order ; the polygon, formed by thefe tangents, is always of a given magnitude in a given Ellipfe, and is equal to a polygon defcribed by a fimilar construction about a circle, the diameter of which is a mean proportional betwixt the tranfverfe and conjugate axis of the Ellipfe.

The polygons inferibed in the Ellipfe, by joining the points of contact (thus formed) and the lectors, bounded by the femi-diametcrs, drawn to thefe points, are alfo of given or determined magnitudes ; and the parts 'of any tangent inter- cepted betwixt the interfections of the other tangents with it, or betwixt thefe interfections and the point of contact, are al- ways in the fame ratio to each other in the fame figure. See Maclaurin's Fluxions, Vol. 1. p. 8. who obferves that there is an analogous property of the other conic Sections.

ELLOTIA, 'JEMwTta, among the Greeks, a feftival in memory of Europa, Agenor's daughter ; who was called 'E?Awti,- by the people of Crete. Ho fin. Lex. univ. in voc.

ELLYCHNIOTOS, in the medical writings of the antients, the name of a fort of tent ufed by the furgeons, and made of cotton or lint, rolled up into the form of the wick of a lamp or candle. See Ellychnium.

ELLYCHNIUM, a name given, by the antients, to that fort of matter, whatever it was, which ferved them in common ufe for the wicks of their lamps, and had, bcfide this, its ufe in furgery. Galen exprefsly directs the ufe of the (oftcft El- lychnuim, fuch as that of Tarfus inftead of fponge, in chirur- gical cafes. But we are far from being afcertained, at prefenr, of what this Ellychnhan of Tarfus was. Pliny mentions feve- ral kinds of Ellyehnia, one compofed of the fruit of the rici- nus, which he particularly commends for its clearnefs ; another of the papyrus, or paper reed ; a third, of the downy matter from the plant called phlomis, and from this ufe of its down, afterwards lychnitis; and fourthly, a kind in which fulphur was a very principal ingredient. He does not, however, give the epithet of Tarfenfe to either of thefe, or tell us of their being invented in, or brought from, Tarfus. Galen is indeed the only author of early date that mentions the Tarfan kind, and that in two places : In the one of which he is talking of bringing ulcers to a cicatrix ; and, in the other, of curing an oedematous fwclling. In the laft cafe he advifes oxycrate to be applied, by wetting with it a fponge, or elfe the Tarfan Ellycbmum. The commentators have gueffed differently as to the meaning of the word ; and Cor- nartus fuppofes it to fignify a fort of fpongy and light fungus, which, when properly wrought up, might be made to fervefor the wicks of lamps, being very inflammable, as we well know many of the fungus's to be, particularly that fort which the people of fome countries call fpunck, and ufe inftead of tinder, to catch fire from the (parks of flint and fteel ; and when in its natural lax ftate, might, by its open lpongy texture, be very wellfuited to imbibe any medicinal fluid, and retain it a lung time, while applied to any difeafed part : Others have gueffed it to be the xylon, or cotton of the antients j but from Galen's propofmg it to be ufed inftead of fponge, it feems much more probable to have been what Cornarius fuppofes. Galen, L. 13 and 14. Cornar. Comment, in 3. x«t. tgtt.

1 ELLIPOMACROSTYLA, in natural hiftory, the name

I of a genus of cryfhls. The word is derived from ibc Greek