B O R 



crack5 a:id lli<-» to pieces before it grows cold. Biirax, when 

 tljua fufed, is called glafs of borax ; by cxpofiire to the air, 

 it acquires the appearance of chalcedony, on account of the 

 partial efflorcfcence that it undergoes. If made in a filver 

 crucible, or i( kijlily melted in an earthen one, it is perfeftly 

 refuluble in water ; but when kept fluid for a long time in a 

 common crucible, it dilTolves a portion of the earth of the 

 Ttll'cl, and becomes little, if at all, foluble in water. 



CryllaUized borax requires twelve parts of water at the 

 common temperature for its folution, but only iix parts of 

 boiling watir; it therefore dcpofits cryllals by mere cooling. 

 Borax is decompofable by all the mineral and vegetable 

 acids when added to excefs, tUe boracic acid belni; ftparattd, 

 ind the foda uniting .ith the other acid ; but if only the ex- 

 cefs of fodn is combined with the other acid, the whole, by 

 evaporation and cooling, forms a confufedly cryllallr/.cd mafs, 

 coiililUng «f the three ingredients in mutual combination. 

 liorax will alfo diflolve and combine with nearly half its 

 wtiglit of boracic acid, forminj; bornt of loda. In this fait 

 the acid and alLaline parts completely fuurate each other, 

 fo that it produces no change on fyrup of \iolets, neither does 

 it polVefi any longer an alkaline talte ; it does not efflorelct- like 

 common borax, nor are the forms of its cryllals the lame. 

 The affinity of foda for boracic acid is not fo great as that 

 of bai7tes, (Irontian, lime, and niagnefia. I'liefe alkaline 

 earths, therefore, decompofc borax ; the pure alkali remain- 

 ing in folution, and the earthy borats forming pulverulent m- 

 foluble falls. Potalh is alfo capable of dccompoling borax ; 

 but borat of potarti being very foluble in foda, iw precipi- 

 tation takes place. 



Silcx and alumine combine in the dry way with borax, 

 the former into a tranfparent, the latter into an opaque 

 glafs. If the ingredients are in nearly equal proportions, 

 the glafs is infoluble in the mineral acids ; but if a conlider- 

 able" excefs of borax is employed, the rcfult is a foluble 

 glafs. Of this circumibnce ^ir. Chenevix has inguuo\ifly 

 taken advantage by fubftituting borax for canllic potnlh in 

 the analyfis of the more refra>5lory llony compounds, the 

 ufe of the former fah being much more convenient, on many 

 accounts, than of the latter. Borax will alfo diffolve moll 

 ©f the metallic oxyds, receiving from each peculiar tinges of 

 eolonr. 



The ufes of borax arc confiderable ; it is employed in the 

 laboratory as a very adlivc flux, and as producing a more 

 perfeftly limpid fulion than any oiher fubHancs. For the 

 fame rcafon it is an ingredient in fome of the finer kinds of 

 glafs ; though its dearnefs prevents it from being employed 

 fo often as it otherwife might be to great advantage. Borax 

 is alfo highly ufefnl to the jewellers and goldfmitlis, as a flux 

 for the folder, by wiiieh pieces of gold and filver are ce- 

 mented together; and in tl'.e End Indies it is employed in 

 the moid wav as a fobxnt for gum lac. 



30 RBE'i'O MAGUS, in y/nmv;/ Geography, IVurms, a 

 town of Germany, according to Ptolemy, who fays, it be- 

 longed to the Vangioni. It was their capital. See 

 Worms. 



BORBO, in Geography, a river of Piedmont, which dif- 

 charges itfelf into the Tanaro at AlU. 



BORBONIA, in Jietuny, (in honour of Gallon Bourbon, 

 duke of Orleans,) a name firit given by Plumier to ( lants of 

 different characters, afterwards transferred by LiniiKiis to a 

 genus in his clafs diail.lpbia ilicaiulna, which is oblcurely 

 dctincd, and concerning which there are in authors mucli 

 confnfion and inconfilVeiicy. L.a Marck fays, that it differs 

 from genilla,only in having the fegments of its calyx a little 

 longer and Iharper, which is fiirely a flight and indetermi- 

 nable circumllaiice ; and from afpalathus, in not having its 



B O R 



leaves fafciculated, which is certainly no generic charaacr 

 at all. He follows Linnaeus, however, in keeping thefe 

 three genera dillinft, but unites it with liparia, from which 

 he finds no reafon to feparate it. Linijxus attributes to it 

 only nine llamens, all united, and obfeiVes, that liparia (a 

 genus formed by him, late in life, from Tlninberg's plants, 

 coUeded at the cape of Good Hope) differs from it m 

 having a tenth feparate ilamen. Bofc fays, that the bor- 

 bonia'has either nine or ten ilamens, eight or nine of which 

 are united at their bafe. La Marck, wiihout noticing Lin- 

 noius's dilliiiftion, aferibes to his united genera ten diadel- 

 phous ftamens ; but it ought to be remarked, that all his 

 dcfcriptions are confeflldly made from dried fpecimens, and 

 Bofc informs us that none of the fpecics are now cultivated 

 in the Paris gardens. In this (late of uncertainty we fl^all 

 follow Willdenow in retaining the Linnsean diltributioii. 

 Linn. S;-;;. Schreb. 1165. \yillden. 1.329. Julf. 85J. 

 Nat. Ord. P apilhmaceie — Legumiiwfn:. Jud. 



Gen. Char. Cal. perianth one-le^ftd, femiquinquefid, tur- 

 binate, half the length of the corolla ; fegments lanceolate, 

 acuminate, rigid, pungent, uearly equal, the lower one the 

 longeil. 6V. pentapetalous, papilionaceous, hirfute on the 

 outfide, banner reflefted, obtufe, claw the length of the 

 calyx ; wings femicordate, a little (liorter than the banner ; 

 keel two-petalled, hinulate, obtufe. Stam. filaments nine, 

 united into a cylinder, dehifcent longitudinally above, rifing 

 at tlie end ; anthers fmall. P'ljt. germ fubulate ; ftyle very 

 <hort, afcending ; lligma obtufe, emarginate. Pcricaip. 

 legume roundifli, acuminate, one-celled, mucronate with a 

 fpine. Seed kidney -form. 



Eff. Char. Cal. acuminate-fpiny. Shgma emarginate. 

 Legume mucronate. 



Species, i. 'Q. eric'ifol'm. Liun. "Leaves nearly linear, 

 acute, villofc beneath, heads terminal." A fmall, rather 

 villofe fhrub ; leaves alternate, pointed, nervelcfs and fmooth 

 above, villous and .channelled beneath ; flowers yellow, 

 fmall ; legumes fliort, very villous within. Its fpecihc name 

 is not a happy one. a. B. trinervia. Linn. " I^eaves lan- 

 ceolate, three-nerved, very entire." Flowers yellow, termi- 

 nating, each on a feparate peduncle, j. B. angn/lifo/ia. 

 La Marck, with a doubt whether it may not be trine/via of 

 LinncEus. " I..eaves nariow-'.anceolate, tive-nerved, fmooth ; 

 legumens oblong, pedunculate^" A fmall (lirub ; Hems 

 flender, interruptedly angular ; .peduncles tw.o or three at 

 the end of each branch. 4. \j.. Larbata. La Marck (lllud. 

 t. 619). "Leaves lanceolate, many-nerved, clofe-fet, ciliate- 

 bearded, very acute ; flowers villous, fubfeffik." Stem 

 cylindiic, with diverging branches ; leaves imbricated, em- 

 bracing the dcm at their hafe. 5. B. ciliata. Wiilden. 

 '• Leaves cordate, embracing the dem, obtufe, many-nerved, 

 very entire, ciliate." Stem cyliudr-c, fmooth ; leaves an 

 inch long, deeply cordate, ciliate at their margin, with long, 

 flender hairs. Nearly al'ied to the foregoing, if it be more 

 than a variety. 6. B. lancajlata. Linn. " I^eaves lanceo- 

 late, many nei-ved, very entire." ^. B. corJuta. Linn. 

 xoviUfejlia ; I^a Marck, who afTerts that Llnnxus's fynonyms 

 to lanceolata belong to this fpecles. " Leaves cordate, 

 many-nerved, very entire, fmooth ; flowers tomentofe, fub- 

 fedllc." Branches villufe ; leaves terminated by a thorny 

 point, crowded ; fegments of the calyx witli thorny points ; 

 flowers covered externally with a wliite and filky down.; 

 banner brown within, b. B. crenata. Linn. " Leaves cordate, 

 many-nerved, toothed." Stems with triangular, fmooth 

 branches ; leaves feflile, or a little embracing the dem, rc- 

 ticularly veined, ending in a point ; flowers fmouth, pedun- 

 culate, three or four in a kind of raceme at the extremity 

 of each branch ; blades fetaceous. 9. B. parv'ijlora. I^a 



Marck. 



