The new dispensatory: containing I. The elements of pharmaceutical chemistry. II. The materia medica ... III. Pharmaceutical preparations. IV. Medicinal compositions ... Being an attempt to collect and apply the later discoveries to the Dispensatory published by W. Lewis ... / By gentlemen of the Faculty of Edinburgh [i.e. C. Webster and R. Irving].

Date:
1786
    but when it is precipitated from this folution by means of acids it is found to have loll ,ts elalticity. The mineral acids, and efpecially tlm nitrous, are alio capable of ddiolving the vegeto-animal part of the fa- rina. “ The ft arch, amybim, or the amylaceous matter, makes the principal part of the farina. As we before noticed, it is that fine powder depofitccl from the water which has pervaded the entire farina : it is of a oreyi'fh white colour, but can be rendered much whiter by making it undergo a certain degree of fermentation. Starch is infoluble in cold water; but' in hot water, it forms a tranfparent glue: hence the neceffity of employing cold water in feparating it from the vegeto-animal part. Diltilled in t retort, it \ leids an acid phlegm ; and its coal affords, like other vegetables, a fixed alkaline fait. As ftarch forms the greateft part of the farina, it is no dqubt the principal nutritive conltituent in bread. “-The mucous, or rather the mucofo-faccharine matter, is only in very fmall quantity in biead. This fubftance on diftillation is found to exhibit the phenomena of fugar. The ufe of this matter feems to be that of pro- ducing the vinous fermentation : and we may obferve once for all, that the preparation of good bread probably depends on a proper proportion of the three different parts above deferibed ; that is to fay, that the vi- nous fermentation is promoted by the mucofo-faccharine part, the acetous by the flarcli, and the putrid by the gluten vegeto-animale. From different ftates or degrees of thefe feveral ftages of fermentation the qualities of good bread arc very probably derived. What remains on this very im- portant fubjeCt will be taken up when we come to fpeak of wheat in the Materia Medica. 11. Of the Colouring Matter of Vegetables. ** The colouring matter of vegetables feems to be of an intermediate nature between the gummy and refinous parts. It is jn many plants equally well extracted by water and by rectified fpirit: it is alfo, however, procurable in the form of a lake, not at all loluble in either of thefe men- Itrua. It would feem that the colouring-matter, ftridtly ft? called, has hi- therto eluded the refearclies of chemifts. It is only, then, the bafs or nidus, in which the real colouring-matter is embodied, that chemiftry has as yet reached to ; and on the chemical properties of this bafe colours are capable of being extracted by different mentlrua, and of being vari- ously accommodated to the purpofes of dyeing. The fubftance from which the colours of vegetables axe immediately derived, is without doubt a very fubtiic body. Since plants are known to lofe their colour when excluded from the light, there is reafon to think that the immediately colouring fubftance is primarily derived from the matter of the fun, fomehow elabo- rated by vegetable life. “ Many of thefe dyes are evolved or varioufly modified by chemical operations. Thus a colouring matter is fometimes depofited in the form of a fecula during the putrefaction of the vegetable ; in others, it is evol- ved or changed by alum, by acids, or by alkalis. We may alfo obferve, that any part of the vegetable may be the bafe of the colouring-matter. This appears from the folubility of the different dyes in their proper men- ftrua ; and in thefe folutions we have not been able to feparate the real colouring-matter from the bafe in which it is invifeated. After all, then, ii 2 wc
    „ , Elements of Pharmacy. Part. I. mud conclude, that a full inveiligation of this fubjeft more properly So”gs to the fublimcr part, of chemiftry, than to the bofinef. we are at 1 “"The colouring drugs will he confidered in their proper places. “ In fin idling otir hi (lory of the vegetable kingdom, it only remains that we fhould offer fome” General Olfervhtions on the foregoing Principles. x. Essential oils, as-already obferved, are obtainable only from ** few vegetables, and camphor from a much fmaller number : but grofs oil, refin, gum, and faline mater, appear to be common m greater or leis proportion to all; fome abounding more with one, and others with an- z. Tlie fevcral principles are in ntany' cafts intimately combined ; fo as to be extracted together from the fubjedt, by thofe diffolvents, in which fome of them feparately could not be difiblved. Hence watery infufiona and fpirituous tindtures of a plant, contain, refpedtivcly, more than water or fpirit is the proper ddfolvent of. 3. After a plant has been fufficiently infufed in water, all that fpirit extracts from the refiduum may be looked upon as confiding wholly of fuch matter as diredtly belongs to the action ot fpirit And contrary wife, when fpirit is applied firft, all that water extracts afterwards may be looked upon as confifting’only of that matter of which water is the diredl diffolvent. 4. If a-vegetable fubfiance, containing all the principles we have been fpeaking of, be boiled in water, the effential oil, whether fluid or concrete, and the Camphor; and volatile effential ialt, will gradually exhale with the fleam of the water, and may be collected by receiving the fleam in proper veffels placed beyond the adtion of die heat. The other principles not being volatile in this degree of heat, remain-behind : the grofs oil and febaceous matter .float on the top: the gummy and faline fubllance, and a part of the refin, arc diffolved by the water, and may be obtained in a folid form by it raining, the liquor, and expofing it to a gentle heat till the water has exhaled. The reft of the refin. it ill' retained byr the fubjedt, may be extradled by fpirit of wine, and feparated in its proper form by exhaling the fpirit On thefe foundations, moil of the fubilances contain- ed in vegetables may be extracted, and obtained in a pure ftatc, however they may be compounded together in the fubjedt1. 5. Sometimes one or more of the principles is found naturally difengaged from the others, lying in diftindt receptacles within the fubjedt, or extra- vafated and accumulated on the furface. i bus, in the dried roots of angelica-, cut longitudinally, the microfcopc difeovers veins of refin. In the flower-cups of hypericum, and the leaves of tire orange-tree, tranfpa- rent points are dihinguifhed by the naked eye; which on the firft view feem to be holes, but on a clofer examination are found to be little vefi- cles filled with effential oil In the bark of the fir, pine, larch, and iomc other trees, the oily receptacles are extremely numerous, and fo c6- pioufly fupphed with the oily and refinom fluid, that they frequently burft, e.pecially in the warm climates, and difeharge their contents in great quantities. I he acacia tree in Egypt, and the plum and cherry among- ourfolvesj yiwd almoft pure gummy exudations. From a fpecies of afh is fecretci.
    -Cliap, i. Vegetables'. fecreted the (aline fweet fubftance manna; and the only hind of fugar which the ancients were acquainted with, appears to have been a natural exudation from the cane. 6. i he foregoing principles are, fo far as is known, all that naturally exift. in vegetables ; and all that art can extraCl from them, without fuch operations as change their nature, and deftroy their original qualities. In one or more of thefe principles, the colour, imcll, tatle, and medicinal vir- tues, of the fubjeft, are almolt always found concentrated, 7* In lome vegetables, the whole medicinal athvity reiides in one prin- ciple. Thus, in fweet almonds, the only medicinal principle is a grofs oil ; in herfe-radifh root, an efferttial oil ; in jalap root, a re fin ; in marfh- mallow root, a gum; in the leaves of forrel, a'faiinc acid fubftance. 8. Others have one kind of virtue redding in one principle, and ano- ther in another. Thus Peruvian bark has an aftringent refill, and a bit- ter gum ; wormwood, a ftrong-flavoured efleutial oil, and a bitter gum- refin. 9- The grrtfs infipid oils and febaccous matters, the fimple infipid gums, an.d the fweet and acid faline fubftances, appearto nearly agree refpeftive- iy among themfelves, in their medicinal qualities, as well as in their pharmaceutic properties. id- But effential oils, refins, and gum-rdins, differ greatly in different fubjefts. As eilential oils arc univertally the principle of odour in vege- tables, it is obvious that they mull differ in this refpefft as much as the fubjecls from which they are obtained. Refills frequently partake of the oil, and confequerttly of the differences depending thereon ; with this fur- ther diverfitv, that the grofs relinous part often contains other powers than ihofe which re fide in oils. i’hus from wormwood a refin may be pre- pared, containing not only the ftrong fmell and flavour, but likewife the whole bitternefs of the herb ; which lad quality the oil is entirely free from. The bitter., aftringent, purgative, and emetic virtue of vege- tables, refide generally in* different forts of refinous matter, either pure or blended with gummy and faline parts; of which kind of combinations, there are many fo intimate, that the component parts can fcarcely be fe- parated from one another, the whole compound diflolving almoft equally in aqueous audfpirituous meultrua. 11. There are fovne fubftances alfo, which, from their being totally diffoluble in water, and not at all in fpirit, may be judged to be mere gums-; hut which, nevettlielefs, poffels virtues never to be found in the fimple gums. Such are the aftringent gum called acacia, and the purgative gum extracted from aloes. 12. It is fuppofed that vegetables contain certain fubtile principles or prefiding fpirits, different in different plants, of too great tenuity to bp colle£ted in their pure ftatc, and of which oils, gums, and refins are only the matrices or vehicles. This inquiry is foreign ,to the purpofes of phar- macy, which is concerned only about groffer and more fenfible obje&s. When we obtain from an odoriferous plant an effential oil, containing in a frnall compafs the whole fragrance of a large quantity of the fubjeft, our intentions are equally anfwered, whether the lubftatice of the oil be the dire& odorous matter, or whether it has dfffuft-d through it a fragrant principle more fubtile than itfelf. And when this oil, in long keeping, iofes its odour, and becomes a refin, it is equal in regard to the prefent jg 3 . con-
    cOrifiderations, whether the effect happens from the avolation of a fubtilc principle) or from a change produced in the fubltaiice ot the oil itletf. SEC T, II. it Animals. FROM the hiftory we have already given of the vegetable kingdom, our details on animal-fubftanees may, m many particulars, beconfi- derably abridged. All animals are fed on vegetables, either direftlyorby the intervention of other animals. No part of their lubftance is derived from any other fource except water. The fmall quantity of fait ufedby man and fome other animals, is only neceflary as a feafoning or ftimulus to the flomach. As the animal then is derived from the vegetable matter, we accordingly find that the former is capable of being refojyed into the fame principles as thofe of the latter. Thus, by repeated diftillations, we obtain from animal-fubftanees, water, oil, air, an eaiily deftrudlible-falt, and charcoal. Thefe fecohdary principles are by farther proceiTes at length refoluble into the fame proximate principles which we found in vegetables, viz. wa- ter, air, earth, and the principle of inflammability. But though the principles of vegetable and animal fubftanees are at bottom the fame ; yet thefe principles are combined in a very different manner. It is ex- ceedingly rare that animal-fubftanees are capabli of the vinous or acetous fermentations ; and the putrefactive, into which they run remarkably fait, is alfo different in fome particulars from the putrefaction of vegetables: the efcapc of the phlogilton in the toim of light is more evident, and the fmell is much more offenfive, in the putrefaction of animal than of vege- table fubftanees. i he putrefaction of urine is indeed accompanied with a peculiar fetor, by no means lo intolerable as that of other animal matters : this we fuppofe tq be owing to the pungency derived to the effluvia fronx the volatile alkali, and alio from the urine containing lefs inflammable matter than the blood and many other fluids. When analyfed by a de= itrudtive heat, animals afford alfo produces very different from thofe of vegetables: the empyreumatic oil has a particular, and much more fetid o our■; apet toe volatile fait, inftead of being an acid, as it is in moll getables is found to be in animals a volatile alkali. Chemiits h< deed fpoken of an and procurable from animal-fubftanees; and indeed ceuam parts of animal-bodies are found to yield a fait of this kind: but n bv no means holds with ammal-fubftanccs in general; and though the proois to the contrary were even conclude, it is coufefTedlv in fuch fmall Z* 7, “ rLtn defcrve tuy pa!tIcular fome animals, how- JD’hVnE,l CXlftS-VT-0mrbmed rnd ready formcd in their bodies. This i. particularly manreft in feme infects, cfpecially ants, from which an acid them in water. The x ""I' re,tn,hling the vegetable gums, but much more adhefiv- We muff h,"">- p»«* *»a .fce Mr, whichklmto brlkikfo’ ,Me l,tller “ *“» >‘<™" of ".<• « -*• The abldt the ve- lave in- rcfembhng the acetous has been procured by boiling tin fohd parts of animal-bodies, as the mufcles, teguments, and even the bones, when boiled with water, give a L i- a ter or in the liquors of the flomach Tl.* mat«
    matters. It is from the folid parts that the greateft quantity of volatile alkali is obtained; it arifes along with a very fetid empyreumatic oil, from which it is in fome meafure feparated by repeated rectifications. This fait is partly in a fluid, and partly in a concrete ftate ; and from its having been anciently prepared in greateft quantity from the horns of the hart, Tt has been called fait or [pint of hartjhorn. Volatile alkali is, how- ever, procurable from all animals, and from almoft every part of animal- bodies. Though we are fometimes able to procure fixed alkali from an animal cinder, yet it is probable that this fait did not make any part of the living animal, but rather proceeded from the introduftion of fome faline matter, incapable of being aflimilated by the funaions of the living creature. . . , a jn fp-eaking of the fluid parts of animals, we mould firlt examine the general fluid, or blood, from whence, the reft arc fecreted. The blood, which at firlt light appears to be a homogeneou^fluid, is compofed of fe- deral parts, eafily feparable from each other, and which eveu the m.cro- fcope can perceive in its imcoagulated ftate- On allowing it to Hand at reft and be expofed to the air, it ftpafates m.to what are called the ernffe7- nentum and the ferum. The craffamentum, or cruor, chiefly confifts of the red globules, joined together by a third l'ubftance, viz. the coagulable lymph :&the chemical properties of thefe globules are not as yet under- flood; but it appears that it is in thefe that the greateft quantity of the iron found in blood refides. The ferum is a yellowilh fub-vifeid liquor, ha- ving little fen Able tafte or fmeil: at a heat of 1-60 of Farenheit, it is con- verted into a jelly. This coagulation of .the ferum is alfo owing to .ta containing a matter of the fame nature as that in the craflamentum, viz. the coagulable lymph: whatever, then, coagulates ammal-blood, pro- d'uces tffit effedt on this concrefcible part. Several caufes and many chemical fubftanceg, are capable of effecting this coagulation; f^cou- taa of air, heat, alcohol, mineral acids, and their combination, wuh earth”, as alum. ’mi fome of the mc.alic falls. The more perfeS falls are found to prevent the coagulation, fuel, as common fait ano “'■“.'br the fluids ferreted from the blood, there are a great wrjtfy■» raen-and other animals. The excriment.tiom end «duniant finds ar thole which afford in general the greateft quantity of empyreumatic oil: there are alfo fame of the fecreted fluids,^ which on a chemical analyfis yield products in fome mealure pecul.ar Of this kind is the urine; which is fount, to contain n Salkali. dance the noted fait formed from the phofphoric acid and...** The fat. too, has been faid to differ from the Edfo yielding by diftiUyion a ftrong ac'^’ J’"1 " ° combi„ation of'the faline much variety in the quantity and Rate j t inveftigation and other matters in different fecreted of this and other parts of the fubje&. we tl br o immediately my, Phyftologv, and Chemiftry; with all which it is more mimeu y conneded than with the Elements of F bannwc*. ^ n<Jt of them. Animal oils and fats, like the grofs 01 » # g ’ be unitcd felves diffoluble either in water or vinous fPir,t8 ‘ ^ . f d of them . with water by the intervention of gum or mucilage , and molt ^ B 4