Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/578

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SUBSISTENCE, in the military art, is the money paid to the foldiers weekly, not amounting to their full pay, becaufe their clothes, accoutrements, tents, bread, &c. are to be paid; it is likewife the money paid the officers upon ac- compt, till their accompts be made up, which is generally once a year, and then they are paid their arrears. SUBTERRANEAN (Cyd.)^Sv bterr ane an fires. Among the many places where thefe fires are found, England is not wholly without them ; though with us they appear only in the coal countries, and plainly feed on nothing but the upper ftratum of the coal, called by the miners day coal, unlefs where they have by accidents been kindled by actual fires at great depths, or fired downward, by being pent in for room. See Volcano.

They have, in many places, been known to burft out fpon- taneoufly from the finface, and make their courfe both ways from the place along the ftratum. There is no ac- tual native fulphur found there, but there are plenty of the marcafites, to which the fire is probably originally owing ; as we know that thefe ftones, piled up in a heap in the air, will often take fire of tbemfelves.

If at any time a finall quantity of melted fulphur fhould be found in the earth, it is not to be fuppofed to be native there ; for the fire acting on the other marcafites it meets with, may very well melt and feparate the fulphur from them, as is done at Goflelaer, and in fome other places, where the fulphur we commonly ufe is made in that manner by art. It has been faid, that crude fal armoniac is found in the earth in thefe places ; but it is only met with at the mouths of the fire. Where the fmoak afcends in thefe places, there continually arife van: quanties of the vapours of fulphur, as well as fal armoniac; and crufts of the flowers of fulphur, and of fublimed fal armoniac, are found together around thefe openings. The brimftone generally arifes firft, and forms a cruft, under which there is a cruft of fal armoniac. It is remarkable, that in the places where thefe fires have burnt, there are often found cavities in the rocks, contain- ing a white milky liquor of a ftyptic tafte : this is a fort of liquid alum, and yields generally about one half of that fait.

'The fal armoniac is found in confiderable quantities in fome of thefe places, yet its origin is not eafily accounted for on the common principles ; for neither nitre, nor common fait, are found in the earth thereabouts. The fprings alfo, which arife in the neighbourhood of the places where the fire is, have been diligently examined, and no fufpicion of the leaft admixture of fal armoniac appears in them. The water that runs through the ftrata of coal in all thefe countries is vitriolic, and turns black with a decoction of galls. There needs no more than burning pit coal to produce fal armo- niac; for it has been found produced in brick-kilns, where nothing but coals and clay have been laid together : and here it muft be afcribed to the coal alone, no one ever having found it in clay. Phil. Tranf. N° 130. See Fire. We have an account, in the Philofophical Tranfaclions, of a fuhterranean town found at Portici, near Naples, in which many antique ftatues, paintings, and other curiofities, have been found.

This fuhterranean town is probably the antient city of Her- culaneum, which was fwallowed up by an earthquake. See Phil. Tranf. N° 458. fea. 4, 5, and 6. It is remarkable, that fome of the antique paintings found there are as frefh and perfect, as if lately painted. Ibid, feet. 6.

SUBTRACTION. See the article Substraction, Cyd.

SUBVERSIOy^m^/;/, a term ufed by fome authors to ex- prefs a violent vomiting, when what mould pafs through the inteftines is voided conftantly by the mouth.

SUBULARE folium, among botanifts. See Leaf.

SUBULATED leaf, among botanifts. See Leaf.

SUBULO, a term ufed by Pliny for deer two years old. See the article Ferula.

Subulo, in natural hiftory, a word ufed by the antients to exprefs a deer, or flag, at that time of its life when the horns firft begin to appear.

Others have underftood it as the name of the oryx, whofe horn was narrow at the fummit, and thence gradually larger toward the bafe, fo that it refembled the figure of the fubula. This is the fabulous creature called the unicorn, and defcribed as a nimble and terrible animal. But it is certain that no fuch animal ever exifted, as is called by this name, and thus defcribed : the only one-horned animal in the world is the rhinoceros, and this is an unwieldy heavy animal, not at all refembling the characters or figures we have of the fubulo, or oryx.

It is to be obferved, that the fubula of the moft an- tient writers was an inftrument of iron, lharp at the point, ufed in the ftone- quarries to break way through laro-e mafles.

SUCCENTURIATI {Cycl)—\x. is the opinion of Dr. Kerk- ring, and of many fince his time, that thefe are cafes in which there is elaborated a bilious juice, which afterwards, either by the emulgcnt vein, or, as often is the cafe, immediately panes to the cava, and being thence conveyed to the heart,,

raifes there that effervefcence, which Sylvius contends to be" excited in that part by the mixture of a faltim liquor with an acid: for although experience contradicts the convey- ance of the juice out of the liver through the cava, yet that effervefcence in the heart, upon which the whole fyftem of Sylvius is grounded, may ftill hold, if this opinion about the ufe of the fuccenturiati be true. As there needs but very- little leaven to ferment a large mafs, which is in a proper ftate and condition to be fermented, a very minute quantity of fait of tartar, mixed with a very large portion of oil of vi- triol, will occafion not only a very confiderable, but a very lafting fermentation; though a very confiderable quantity of the latter, poured on a quantity of the former, caufes but a languid and fhort effervefcence. This account of an opini- on, though not now received, may be worthy the confide- ration of thofe who remember how cautioufly both fides of a queftion ought to be heard, before any thing is deter- mined in regard to it. Kerkring, Spicileg. Anat.

SUCCIFERA vafa, in natural hiftory, a name given by thofe who have written of the anatomy of plants, to thofe vefTels which contain the juices, by way of diftinction from thofe which only give paflage to the air, and are called trachea. Lewenhoek tells us, that the microfcope difcovers thefucri- ferous veflels of plants to be, in all refpects, analogous to thofe of animals, and that they are of two kinds, veins and arteries : the latter receiving the juices from the root, and carrying them all over the plant ; and the others receiving the juice from their extremities, and carrying it back again to the root, where it is again delivered to the ar- teries.

SUCCINUM, amber (Cyd.) — The origin of amber has been much difputed among the naturalifts, and many erroneous, and fome even abfurd, conjectures made about it. There feems however, from experiment and a clofer obfervation, to be no doubt but that it is wholly of mineral origin, and is a bitumen which was once liquid, and of the naphtha, or petro- leum kind, hardened and brought into its prefent ftate by a mineral acid, of the nature of fpirit of fulphur, or oil of vitriol ; both thefe fubft ances abounding in the earth, and an artificial mixture of them producing a body much refembling amber, and affording all it.3 principles on a chemical ana- lysis.

Flies, and other fmall infects, found bedded in amber, have by fome been fuppofed mere lufus nature, and never to have been real animals ; but this needs only the eye to difcover its abfurdity : and with others, who allow them to be real, they are ufed as proofs that amber is of vegetable origin, and was once foft and fluid. That they do prove the laft is certain, but by no means the firft. To judge properly of this, we ftiould confider the true ftate of the cafe, which is this : that more than a thoufand pieces of amber are found without infects, for one that has any ; and that moft of the pieces which have them, have not been dug out of the earth, but found on the fea fhores. The fides of hills we well know are continually trickling down the liquid bitumens ; and there is no abfurdity in fuppofing, that fmail quantities of this might, in its paflage, be detained in little cavities of rocks, &c. and there fufter le'ifurely its change into amber, from the matter of its natural acid being near. And it can be no wonder that flies, life, fhould be drowned in fuch a mafs of matter, which being afterwards hardened, might be found on the furface of the earth, or wafhed down to the fea, in the form of common amber. Nor is there any thing im- pofiible in the malTes, thus formed on the furface, being af- terwards buried in the earth, by the various changes we know the furface of the earth at times is fubject to. Befide the places whence amber is ufually brought, which are Pruflia, Pomerania, C3V. we have it on our own fhores, and even in our clay-pits ; the pits dug for tile clay, between Tyburn and Kenfington Gravel-pits, have afforded many fpecimens; and that behind St. George's Hofpital, at Hyde- park Corner, has afforded fine fpecimens, one of which has been wrought into a beautiful cane-head of three inches long. Hill's Hift. of Foil", p. 409,

If the people, who collect amber on the fhores of the Baltic, were more curious and particular in their obfervations of the mafles they find, we fhould doubtlefs have much more lights into its true hiftory and nature. There is no queftion, but that fome pieces of it are toffed up there fo imperfectly formed, that the procefs of nature may be feen in their dif- ferent ftages. Pieces have been fometimes found fo foft, as to receive the impreflion of a feal : thefe are always not only perfect amber in other refpects, but they are obferved to have a fmell ftrongcr than the common amber has. Thefe pieces fometimes harden immediately, on being expofed to the air, but fometimes they retain this foftnels many months. We have an account of fuch a piece in the Philofophical Tranfactions, which had retained this foftnefs a whole year, in which time it had lain among other pieces of amber ; and of another mafs very foft on one fide, and hard on the other, and containing in the foft part a fly bu- ried. Phil. Tranf. N° 57. This foflil has been of great repute in the world from the

1 before
 * very earlieft times we have any knowledge of, many years