S P I 



foon as the fkin has become quite brown, the cauilic may be 

 walhed off with forae wet tow, the adhefive plafter may be 

 removed, and the part covered with a linfeed poultice. 



Immediately the efchars are loofe, and can be taken away 

 without pain, the iffues are to be filled with peas, or kidney- 

 beans. Thefe are to be covered with adhefive plafter, 

 which will confine them in their fituation. However, as the 

 hollows foon become filled up with granulations, unlefs con- 

 fiderable preffure be made, it is generally deemed neceffary 

 to bind a piece of pafteboard, or a comprefs containing 

 a bit of Iheet-lead, firmly on the fituation of the iifues. 

 The preffure thus maintained, though creative of uneafinefs 

 at firft, will, in the end, fave the patient an immenfe deal of 

 pain ; for, in confequence of its operation, the peas or 

 beans will foon form as many little hollows in the cavity of 

 the iffue as their own number, and into thefe the future peas 

 may afterwards be put and retained, without the leall unea- 

 finefs, provided the furgeon gives particular injunctions not 

 to allow the bandage to be ever flack. The preffure faves 

 the patient, in the end, a great deal of pain, which would 

 otherwife be unavoidable, on account of the furgeon being 

 neceflitated to reprefs the rifing granulations in the cavity of 

 the iffue, by fprinkling them with powder of cantharides, 

 or the pulv. ex aerug. leris et fabins, or even rubbing them 

 with the cauftic. In moft inllances, however, it is now and 

 then requifite to apply one of the above powders underneath 

 the beans or peas. In order to apply peas advantageouQy, 

 they fliould be previoufly foftened in warm water, and con- 

 nefted together like beads, by palling a thread through their 

 centre. Then they (hould be allowed to become completely 

 dry, when they are fit for immediate ufe. There fhould al- 

 ways be a greater length of thread than of peas, by which 

 means, two little portions at the ends of the peas may ex- 

 tend beyond each extremity of the iffue, and be fixed there 

 by two fmall bits of adhefive plafter. This little contrivance 

 will have great effeft in keeping the whole row of peas in 

 its right fituation. When the iffue is more than half an inch 

 in breadth, two rows of peas {hould be placed in it. 



It is faid that a ftring of beads anfwers quite as well as one 

 of peas or beans, and certainly it is more convenient, as, 

 when regularly waftied every day, it may be ufed as long as 

 the furgeoB thinks proper ; and thus the trouble and expence 

 of getting frelh peas or beans may be avoided. 



The iflues are to be kept open until the cure is complete ; 

 that is, until the patient perfeftly recovers the ufe of his 

 legs, or even for fome time afterwards. Mr. Pott judicioufly 

 recommends the praftitioner to heal at firft only one of 

 them. 



In conjunftion with the iffues, bark, fea-air, and fea- 

 bathing, are frequently proper. 



There have been various contrivances propofed for the pur- 

 pofe of affording mechanical fupport to the fpine. This 

 method does not, however, promife to be ufeful. When the 

 morbid affeftionof the corpora vertebrarum has advanced to 

 a certain ftate, the adjoining found bones, both above and 

 below the feat of the difeafe, become approximated to each 

 other, and at length anchylofed. This falutary procefs, if 

 influenced at all by mechanically fupporting the fpine, muft 

 obvioufly be retarded. From this account we alfo fee the 

 reafon why the projeftion of the fpinous proceffes, at leaft 

 in adult fubjefts, muft always remain. In children, however, 

 a great diminution, and even an entire removal of a certain 

 degree of deformity, may take place during the growth of 

 the body. Pott's Chirurgical Works, vol. iii. Cooper's 

 Firft Lines of the Praftice of Surgery, edh. 3, part 2. 



Spine, in Agruullure, a term fignifying provincially the 

 furface turf, fod, or fward of land. 



S P 1 



Spine, a (harp, firm, hard point which is fent off from 

 the woody parts of fome forts of plants. It confequently 

 differs from a prickle, which only rifes from the bark of the- 

 plant. The fpines in plants of this nature are produced 

 either fingly, as is the cafe in moft of them ; doubly, or by 

 pairs, as in fome particular forts ; or in a triple manner, a? 

 in the three-thorned acacia. 



Spines of Echini, in Natural Hifiory. Thefe in their foffile 

 ftate make a great appearance in the cabinets of the curious, 

 and in the works of the learned, and are of an almoll infi- 

 nite variety of kinds ; and many of them are of the fame 

 figures and dimenfions with thofe of the echini now hving 

 in our own and other feas, and well known to us. But be- 

 fide thefe, there is an almoft infinite variety of others, which, 

 though allowed on all hands to be truly fpines of fome 

 echini or other, yet evidently differ from thofe of all the 

 known recent fi(h of that name, and have certainly belonged 

 to a fpecies of it, of which we have not now the leaft know- 

 ledge. Thefe, however different in fhape from one another, 

 yet all agree in their texture and conftituent matter. 



SPINEDA, in Geography, a town of Italy, in the de- 

 partment of the Upper Po ; 4 miles N.N.E. of Sabionetta. 



SPINELL, or True Ruby, Spinelle of Haiiy and Broch, 

 in Mineralogy. (See Gems.) The colour of this gem is red, 

 blended with tints of blue or yellow ; and it occurs in grains, 

 in fmall rounded fragments, and cryilallized. The primitive 

 form of its cryftals is the regular oAohedron, exhibiting alfo 

 the varieties of the cuneiform oclohedron, the primitive odo- 

 hedron with the edges of the common bafe truncated, the 

 fame with all the edges truncated, and the primitive oftohe- 

 dron divided obliquely into two fegmcnts, which are turned 

 on each other il-th of a circle, thus forming a folid with al- 

 ternate faliant and re-entering angles. The cryftals are fmall 

 and very fmall, rarely middle-fized. The faces of the odo- 

 hedron are fmooth, and the planes of the truncatures are 

 longitudinally ftriated. Its luftre, externally and internally, 

 is brightly fliining, vitreous. Its crofs frafture is conchoi- 

 dal, its longitudinal fradurc is lamellar in three direftions. 

 It varies from tranflucent to tranfparent. It is confiderably 

 hard, though in this refpeft inferior to fapphire. Sp. gr. 

 5 ry — 3.64. Before the blowpipe it is infufible without 

 addition, but melts with borax, acquiring a green colour. 

 When ground to a very fine powder, it is foluble by long 

 dio-eftion in boiling fulphuric acid. It was firil analyfed by 

 Klaproth, and afterwards by Vauquehn, with the following 

 refults : 



Klaproill. Vaiiqut-liit. 



Alumine - 74.5 82.47 



Silex - -^55 o. 



Magnefia - 8.25 8.78 



Oxyd of iron 1.5 o. 



Lime - - 0.75 o. 



Chromic acid - o. 6.18 



100.50 



97-43 



Although its geological fituation is not known, it occurs 

 imbedded in calcareous fpar and adulaiia, accompanied by 

 mica and magnetic pyrites. See Gems. See alfo Corun- 

 dum. Aikin's Dift. 



Mineralogifts formerly clalfed all varieties of ruby with 

 fpinell, and alfo the oriental ruby or fapphire. The cochineal- 

 red variety of fpinell is the Balais ruby of the jewellers, fo 

 called from Balachan, the Indian name of Pegu, where it is 

 found. The violet-blue fpinell is the almandine of Pliny ; it 

 is named from Alabanda, a town in Leffer Afia. The orange- 

 yellow variety is the rubicelle ruby of jewellers. A newly 



difcovered 



