The Edinburgh new dispensatory : with explanatory, critical, and practical observations on each : together with the addition of those formulae, from the best foreign pharmacopoeias, which are held in highest esteem in other parts of Europe ; the whole interspersed with practical cautions and observations, and enriched by the latest discoveries in natural history, chemistry, and medicine ; with new tables of elective attractions, of antimony, of mercury, &c. ; and copperplates of the most convenient furnaces, and principal pharmaceutical instruments ; being an improvement upon the New dispensatory of Dr. Lewis.

  • Lewis, William, 1708-1781.
Date:
MDCCXCI [1791]
Catalogue details

Licence: Public Domain Mark

Credit: The Edinburgh new dispensatory : with explanatory, critical, and practical observations on each : together with the addition of those formulae, from the best foreign pharmacopoeias, which are held in highest esteem in other parts of Europe ; the whole interspersed with practical cautions and observations, and enriched by the latest discoveries in natural history, chemistry, and medicine ; with new tables of elective attractions, of antimony, of mercury, &c. ; and copperplates of the most convenient furnaces, and principal pharmaceutical instruments ; being an improvement upon the New dispensatory of Dr. Lewis. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    We now come to the laft, but perhaps the raoft generally diffufed, acid in nature : this is the aerial acid, or Fixed Air. In our pharmaceutical hiftory of this body, we fhall only make ufe of the two names,/.W air and aerial acid, being thofe mofl generally ufed, and which in our opinion are mofl: applicable to our own fubject. Fixed air is a permanently elaftic fluid, being only fixed when in a (late of com- bination with calcareous earth or other fubftances from which it may be extricated. It has received many different names, according to the fub- ftances from which it is difengaged, and the different opinions concern- ing its nature ; it is the gas filveftre of Helmont, the fixed air of Dr Black, the acid of chalk, calcareous gas, mephitic gas, mephitic acid, and aerial acid, of many modern chemifts. In accommodating our account of it to the purpofes of pharmacy, it is mofl; convenient to confider it in the light of an acid. The aerial acid, then, may be extricated by heat, or by other acids, from all calcareous earths ; that is, from all thofe earths which by calcination are converted into quicklime; fuch as chalk, mar- ble, limeftone, fea-ftiells, &c. It is likevvifc extricated from mild, fixed, and volatile alkalies, and from the magnefia alba. Thus, if the vitriolic, or almoft any other acid, be added to any quantity of calcareous earth or mild alkali, a brilk effervefcence immediately enfues ; the fixed air, or aerial acid, is difcharged in bubbles ; and the other acid takes its place. If this procefs be conducted with an apparatus to be afterwards defcribed, the aerial acid, now feparated from the calcareous earth, may be receiv- ed and preferved in clofe veflels. When thus difengaged, it aflumes its real character, viz. that of a permanently elajlic fluid. Fixed air is alfo feparated in great quantity during the vinous fermentation of vegetable matters. When a calcareous earth is deprived of this acid by heat, it is converted into thecauflic fubftance, quicklime. When alkalies, fixed or volatile, are deprived by any means of their aerial acid, they are render- ed much mofe cauftic, incapable of cryftallifation, or of effervefcing with other acids. They are alfo in this <&■«<?>*#?</ftate much more powerful in diflblving other bodies. By recombining this acid to the quicklime, the calcined magnefia, or to the alkali, any of which had been deprived of it, thefe fubftances again aflurne their former weight and properties. Thefe bodies, then, when combined with aerial acid, are called mild ,- as mild calcareous earth, ??iild alkali, &c.: and when deprived of this a- cid, they are called cau/fic; as cauftic calcareous earths, cauftic, alkali, Sec. but as magnefia is not rendered cauftic by calcination, there would per- haps be lefs danger in calling them aerated and dea'erated. The aerial a- cid is more difpofed tounite with cauftic calcareous earth (quicklime)tban with any other fubftance ; next to that, its attraction ftands for fixed al- kali ; then with magnefia; and, laftly, with volatile alkali. We fhall af- terwards find, that thefe relative powers of the different fubftances to unite with this acid, lay the foundation of many important procefles in pharmacy. When we pour a fmall quantity of the aerial acid into lime-water, the liquor inftantly aflumes a white colour, and the lime gradually precipi- tates, leaving the water clear and taftelefs : the lime in this experiment has ablbrbed the acid, and has therefore become mild or aerated earth. The ae'rial acid is capable of being abforbed by water ; and the water E thus