장음표시 사용
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under the nante of Lahes. These are truly pre- cipitates of the colouring matter, in Combina- tion xvith various mordents as their bases.
The colouring of the bones of a living ani- mal, by the use of mander, is in eVery CircUm- lance analogoris to the formation of these lahes. The colouring matter of the madder, passing unaltered through the digestive organs of the animal, enters the generat masi os su-
ids, and is dissolved in the serum of the blood; to whicli, in deed, is it be in large proportion,
it communicates a very sensibiy red tinge But there is always present in the blood, and in a state of solution in the serum, a quantity of the earthy matter of the bones, phosphate of lime, ready tobe deposited, as the eXigeiacies of the animal shali require. NON, the phosphate of lime is an excellent mordent to madder, haS RU strong assini ty to it, and consequently is admi- rably fitted to a Iord a base to the colouring matter of it. In luch experimenis, therei ore, they concrete in tho sate os a b right redo luke,
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lahe, Wheiace the colour of the bones is de-
That this is actualty the case may be sine n by various eXperiments. Thus, is to an insu- sion os madder, in distilled water, be added a litile of the muriate of lime, no Change i8 per- ceived; but is to this mixture be added a so- lution of the phosphate of soda, immediately a doubie elective attraction tines placer The muriatic acid, combining with the soda, re- mains suspended or dissolved in the water; while the phosphoric acid, thus deprived of iis soda, combines With the lime, whicli the muria- tic acid had parte d with, and forins phosphate of lime, or earth of bones. This substance be- in g, however, insolubie in Water, talis to the
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From this simple representation of the mat- ter, IVe have a ready eXplicatiora os every cir cumstance that has been re mained as eXtraor-
se more quichly, and more deeply tinged than the bones of older animais Why the bones acquire a very deep tinge When perhaps the serum of the blood has not acquired any sen- si1ble colour Dom the madder Why the har- der paris of the bones are most deeply tinged -Why somelimes a bone seenas motiled or spolied Why the enamel of the ieeth receives no Colour because there is in lach no change ' in that substance, with respeet to ei ther secre- tion or absorption, after it is once formed. But it by no means follows, that the enamelos the ieeth may not acquire a tinge in thes Ame manner as the earth of bones, provided
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or other such tinging materiat, at the time that the ena mel isse reted. or sirst assumes a Concrete forni; as in young animais While their ieeth are just in a na scent or incipient state ; or perhaps bet ter, in the foetus in utero, ViZ. by miX- ing the tinging materials plentifully with the food of the mollier during her gestation. But even though the en amel siould acquire a tinge m such triais; it may weli be, that this tinge mali be very different frona that acquir- ed at the fame time by the bones: For as the structure and composition of the enamel is dif- ferent Dom those of the fibro us or e thy part of the bones, it is lihely that it may havea disterent essest in modii ying the colouring rnat ter of madder; both With respeet to the particular tint or species of colour, and the particular stade or intensity of it: Iust as u e frid, that with the sume coloured infusion, by employing dicterent mordents or bases, vario us' i kes may be obtained.
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It is natural to conclude, that there may hemany Vegetable substances, whicli, like the roots of madder, are possessed of the quality of communicating a particular Colour to the hones of living animais, such as the particular substance employed gives to other bodies; and We may attain to almost absolute certainty in this matter, by such an eXperiment as that just
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intestinat canal, Without having undergone u very great change in respect of their colour. The Genipa Americana may be of this nature, the pulp irrounding the seeds of whicli, is salil to stain animal matters of an indelible blue. VΡlurima eXperimenta de compositione corticis sinati feci, eam Calori et aliis examinibus subji- .ciendo, et eX hisce ex materie ab ossis veri materie diversa, nempe eX Calcis Carbonate, potissimum Constare mihi videtur. Ex his observationibus manifestum est, pUIVerem simplicissimum et optime pioepar tUm, deD-tibus frequenter applicatum, corticem striatum detere Ie, periclitari. Usque ad hoc tempus pul- velis solius applicatione dentium Curatores non contenti, Ope mellis, &C. in glutinum eum formant, Unde Vis ejus agendi multum augetur, dentes multo Citius aIbos reddit, superficiemque Corticis striati politam deterit.
Cremor tartari pulverum, pro dentibus abstergendis venditorum, frequentissime partem Consat. Dentium corticem striatum prorsus detri-
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tum vel solutum ejus actione, hominesque inde miseros redditos, novi : Namque sensilis tac- tui levissimo pars ossea fit: Et quidem Cremor tartari solus adhibitus est, et laudatus a D. I. HUNTER. Ρericulum simpleX, quod sequitur, quodque facile iterari potest, ad ejus modum a
gendi detegendum feci. Dentem in Cremoris tartari ex aqua communi solutionem immersi; post duodecim circiter horas, superficiem CortiCis striati asperrimam, et crystallis eX propria ejus materia et acido tartaro, tartritide scit. Calcis, Conflatis, omnino obductam laetus inveni. CorteX stilatus sola pars affecta videtur, quamvis pars ossea a nonnullis crystassorum Cooperitur. Quomodo hoc fit, perspicuum est ; acidum enim tartareum magis ussine est terrae calcareae quam potasAE; ideoque corticem striatum, qui illius nature est, ad se rapit, relicta simul potassa: ita, igitur, formatur tartris Calcis, quae in aqua ferme insolubilis, brevi sub forma crystallorum deponitur. Notandum p terea quod in tartaro acidum tartareum praevalet, ad saturandam potassam. Hinc intel
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ligi potest, quam facile corticem striatum, etiamsi
non omnino deComponeretur, solveret. Cum Vero pro Cremore tartari acidum ipsum tartarosum substituitur eodem temporis spatio, crystalli multo majores formantur. Essentiae et lotiones quoque variae adhibitae sunt, quarum multae quaedam acida Continent, et quamvis parCe forsan, tamen cum assidua sit earum applicatio, quin dentes non solvant et vitient, non potest. Ut paucis absolvam, parentes et tutores omnes niti debent, infantes ut dentes quotidie, scit. mane et Vespere aqua simplice abluant et abstergant ope instrumenti, Ang. Dotbbrusi. dicti. Si vero dentes eorum Vel gingivae Vitiantur, quam primum arcessendi sunt ii quos penes est dentium Curatio.
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PROPTgn delicatam corporis humani structuram, omnibus vitae temporibus innumeris fere malis obnoxium est; sed ob insignem infantiae irritabilitatem tum magis quam Ullo alio tempore a causis, etiam levissimis, assici periclitatur. Plurima igitur mala praecipue primis artatis annis invadere solent; quo sc. tempore dentes e maXillis emergere ob serVantur. Hac temporis convenientia seducti medici utrosque inter affectus nexum arctum intercedere opinati sunt; atque exinde ad assectiones morbosas, tunc praesertim oriundas, explicandas, theoriam concinnaverunt, quae certe prae aliis majori hominum parti arrisit ;nempi has a sectiones violentibus conatibus dentis per gingivam erumpentis, Vel erupturi, CZΠ-demque lacerantis, ascribendas esse. IIaec opinio Per longam annorum seriem ab uno ad alterum si tra-
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tradita est ; eique credunt plerique medici tam antiqui quam hodierni; at sine harum partium satis accurata examinatione, quae e sectionibus solummodo acquiri potuit. Nisi limites, qui hujusmodi dissertationibus vulgo praescribuntur, jam pridem transiissem, plurimas observationes ad opinionem eorum stabiliendam per scripta diffusas, collegissem : in praesentia
tamen pauca tantum harum opinionum capita percurram, ut, quam sibimet invicem obsint, quamque fallaces inductiones inde deducantur, monstrare pOL sim. Sic dixit H1PPOCRAT Εs '; dentes caninos erupturos vehementissimas affectiones gignere. Bo-ΕRHAAVIUS ' autem Omne8 dentes acutos tales similiter inducturos opinatur ; sed commentator ejus VAN SCI ΕΤΕΝ rationem, valde speciosam facilitatis, qua alii dentes prae aliis erumpunt, reddere conatur, verbis quae sequuntur. ς ς ε Cum ς autem omnia haec mala a tensione, punctura, la-