Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/515

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and of Cruftaccous external figures. And 2. the placagno- fcuria, opake cruftaceous /pars of an irregular ftru£tuie within.

Of the eighth order there are two genera, i, The cihde- lojlracia, terrene /pars, found in form of thin plates on the furfaces of fiffures in ftone quarries. And 2. cibdelsplacia, terrene/pars, ufually found coating over vegetable, or other extraneous matter in fprings, c5V.

Of the ninth order there are two genera. I. Thejlalafiav- nia, cryftalline /parry ftalaflitae. And 2, ftalaBt-cibdcIa, cryftallino-terrene, /parry ftalactitas.

And of the tenth order there are alfo two genera, i. The Jialapnodiaugia, or pellucid /parry ftalagmita. 2. Stalag- mofcieria, dull and opikc/parry ftalagmitae. SHU'S Hiil. of Foffils, p. 203.

The obfervation that /par is continually formed at this time in caves and grottos under ground, has given birth to many different conjectures as to the origin of that fubftance. We have accounts from Swiffcrland, and other places, that the fnow by long lying on the earth, and being fubject to re- peated freezing, is at length hardened into /par : this is much of the nature of that opinion of the antients concern- ing cryftal, that it was water frozen by fevere colds to a fort of ice, much harder than the common kind ; both are equally erroneous and abfurd. But more rational conjectures, as to its origin, are, that it is produced either by effluvia alone, or by the joint force of effluvia ifl'uing up from the depths of the earth, and mixing with water ouzing out of rocks into their cracks and cavities, or by the fame water or effluvia paffmg through beds of this /parry matter con- tained in clay. In the firft place we are to obferve, that /par is capable of being diffolved either by water or vapour, and fufpended. imperceptibly in either ; and that though it remains fufpended a long time, yet there are occafions of its feparating itfelf from either of thefe vehicles, fuch are long Handing (fill, and evaporation. What is called the Growth and formation of /par, therefore, is properly perhaps only the change of place in this fubftance, and all that thefe agents, water and vapours, do, is only to wafti it out of the ftrata of earth or ftone, in which it lay in fcattered particles, and bring it together into the cracks and crevices of ftones', where it may again feparate itfelf, and become more pure and perfect. The operation of nature, in this cafe, is very like that of art in the extracting of falts from the various! bodies they are mixed with ; and [par in its two ftates, when blended in the ftrata of ftone, isc. and when pure, and in form of cryftals in the cracks, may be compared to alum, for inftance, in its bed, and when purified. The alum in the common ftones, from which it is made, is not percep- tible to the eye, but lies in fcattered particles ; water being added to this takes up the fait, and when it has been ma- naged by evaporation and reft, yields it again purified and alone, and it forms fuch cryftals on the fides of the vefl'el as the other does on the fides of the fiffures of ftone, which are the veffels where the water, out of which it was formed, was fet to evaporate, and to reft a proper. time. That fome /pars grow from vapours alone, is evident from the Jia- laklitte, or ftony icicles, hanging down from the roofs of our caverns, which, though they grow downwards, yet have many times little plants of the fame fubftance growing out at their fides, and ftanding upwards, contrary to the growth of the other, and evidently formed of the matter feparatcd from the vapours in their afcent, as the ftaladtita: themfelvcs are from fuch as have afcended to the roof, and there been condenfed into water, and fent down again in drops. Nor is the /parry matter alone thus raifed in vapour, for even the metals, and other bodies, as little likely as thofe to be thus raifed, yet are found to form ftalactitae. The mundics in general, though they never form regular ftalaaitK, yet often are found adhering to the fides of them, and the me- tals, particularly iron and lead, form regular ftalafiitae ; the iron ones very common, and very perfect ; the lead lefs perfect, and more rare ; and Dr. Brown gives us abundant inftances, of /pars growing entirely from vapours in the baths of Buda in Hungary. Phil. Tranf. N° 129. Mr. Beaumont b is of opinion, that earth by degrees will ripen into /par ; but this is an error. He founds his opinion on certain ftalactitae, and ftalagmitae, found in caverns, partly earth and partly /par, and fuppofes, that the whole would in time become /par ; but there is nothing in nature

to warrant this conjecture [' Phil. Tranf. ibid. J

Mr. de Juffieu has given us, in the Memoirs of' the Pari: Academy, a very remarkable account of the recryftallization or reproduction of the parts of /par, after folution, in th< following inftance.

There are found in the mines near St. Bell, where they dig copper-ore, a fort of ftones, which ufually cover the vein of the ore ; thefe are compofed of feveral flat plates laid evenly on one another, as our rhomboidal and parallellopiped /pars, and thefe, as the diftinctions of foffils were not at that time eftablifhed, the author called, from their eafy calcina- tion, a fort of gypfum, w.hich he diftinguifhed from the reft by their plated ftructure. They are white on their outfidc, and greyilh. within ; and their internal part being heavy, and Suppl. Vol. II.

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full of fpariding points, they Were fuppofed to contain forh* copper and were thrown into the furnace ufed for roaftimr the other ftones in which copper was lodged. The caici° nation reduced thefe ftones into a fort of plafter, or gypfum, After this thefe calcined ftones, which were now as red as colcothar of vitriol, were thrown into tubs,, and large quan- tities of water were poured on them; this took up their cupreous, their vitriolic, and their /parry particles. From tnele tubs the impregnated liquor was let out into a bafon, in rile midft of which were placed feveral pieces of iron ; thefe were all immediately changed in appearance into cop- per by the liquor. The liquor fent up all this while a thick white vapour, which covered all its furfacc, and arofe to the height of a foot above the edge of the bafon. This vapour by degrees diflipated itfelf into air; but where it had touch- ed, not only the fides of the bafon that were above the fur- face of the liquor, but alfo the earth about the edges, were covered with fmall regular cryftals, of a figure approaching to a parallellopiped, and of an infipid tafte, in fbme degree traufparent, and very thin and flat in proportion to their breadth or length. Thefe were the fingle cryftals, but the continual formation of them, one upon another, at length formed of them concrete maffes, refembling large cakes of

!? r n t - a r,, Thefe Were Iike the other a true fP« r > bein? 'n- dilioluble in water, and eafily calcining in the fire, and hav- ing all the other qualities of the ftones from which they were originally obtained. This procefs is the more lingular, as calcination is a very ftrange method of procuring the cryftals of a body, and in this fubftance feems entirely to deftroy them in their original ftate ; fo that chance alone could have dlfcovered a property of their rifmg in vapour from this, and again affuming their proper form; but it would deferve a trial whether the common /pars, which will recryftalhze after folution in the acid menftrua, will alfo do it after calcination. Mem. Acad. Par. 1719. Spars, in medicine, have from the earlieft times been recom- mended in nephritic complaints. Some have ufed one kind, fome another, as the lapis judaims, the /parry incruftations of caverns, petrified oyfter-fhells, and water in which lar»e quantities of /par are fuftained. After all, the nephritic virtues of /par want fufficient proof; fome even fufpeaits ufe to be more hurtful than beneficial. See Crystal. It were to be wifhed, that whoever attempts to afcertain this point,would choofe for the experiment fome determinate kind of /par in its natural form, rather than under appear- ances, whereby its efficacy may be confounded with that of other bodies. See the articles Belemnites and Ostra-

CITES.

SPARAGUS, or Asparagus, fperage, in botany. See tho articles Asparagus and Sperage.

SPARGANOSIS, a word ufed by fome to exprefs a milk- tumor in women's breafts.

SPARGUS, in ichthyology, a name given by Gaza to the common fparus, which he calls alfo ftuta. Artedi calls it the plain yellow /parus with an annular fpot near the tail. See Sparus.

SPARLING-/™/, in zoology, a harhe given in fome places by the country people to the female merganfer, called mora ufually the iundltiit. This fo much differs from the male of the fame fpecies, as to have deceived the generality of authors into thinking it a different bird.

SPARRING, or Sparing, amohg cock-fighters, a term ufed to fignify the fighting of a cock with another to breathe him j in which fights they put hotts on their fours, that they may not hurt one another. Sportfm. Did. in voc. See the ar- ticle Hotts.

SPARROW, in zoology. See the article Passer.

Sparrow-^™/}, in botany, &c. See Asparagus.

SPAR.SE-/Wj, /par/a foiia, among botariifts. See Leaf.

SPARTIUM, in botany, the name of a genus of plants, the charaflers of which are thefe. The flower is of the pa- pilionaceous kind; the piftil, which arifes from the cup, fi- nally becomes a fhort roundifh turgid pod, which ufually contains a kidney-fhaped feed.

The fpecies of /partium, enumerated by Mr. Tournefort, are thefe. 1. The yellow- flowered /partium with a kidney- fhaped feed. 2. The white-flowered Spanifh /partium. 3. The prickly ebony-like purfelain-leaved American /par- tium. And 4. the climbing citron-leaved American /partium with white flowers growing in clutters at the joints. Tmrn. Inft. p. 645.

SPARTOPOLIAS lapis, in natural hiftory, a name given by fome authors to a whitifh agate, variegated with long and (lender flreaks of grey difpofed in a varioufly undulated or- der, and refemblihg grey hairs.

SPARUS, in the Linnsean fyftem of zoology, the name of a genus of fifties of the general order of the acauthoptervgii, the charaflers of which are, that the opercula of the 'gills are fcaly, and the mouth is furnifhed with grinders coveted with lips. Of this genus are the farg'us, canthafus, me- Ianurus, &c. Linmsi Syft. Nat. p. 54. In the Artedian fyftem of ichthyology, the charaflers of this genus of fifties are thefe. The coverings of the gills are fcaly. The teeth are covered with lips, as in quadrupeds. J X x x 'The