18230 Mr, GrayH Elements of Pharmacy, 461 



7. Fat and oily bodies. 



8. Sweet bodies. 



9. Acrid bodies. 



It will, perhaps, be scarcely credited when we state, that 

 the first *' combustible drug," which its *' taste " has assigned 

 a place among the earthy and absorbent bodies, is incombusti- 

 ble and tasteless. When treating of " the earthy and absorbent 

 bodies," Mr. Gray says, " only one compound combustible 

 substance of this kind is now quoted in the London Pharmaco- 

 pceia, namely, testae. 



" Testa, — Oyster shells consist of carbonate of lime deposited 

 in a tissue of gelatinous matter, which latter is very small in 

 quantity ; hence they are used only as antacids. On calcina- 

 tion, the gelatinous matter is burned, the carbonic is driven off, 

 and a pure lime remains." Now as chalk is quoted in the 

 London Pharmacopoeia, as well as oyster shells, the reader will 

 wonder with us how it happened not to be arranged with the eafthy 

 and absorbent bodies ; it is true that it has no taste, and is not 

 combustible ; but it is at least as sapid and as combustible as 

 oyster shells ; the reason we suppose to be, that as shell contains 

 a small quantity of gelatinous matter which is combustible, but 

 to which it owes none of its absorbent powers, it is ranked among 

 the compound combustibles. We think we need scarcely ask, 

 whether any arrangement can be essentially good which separates 

 two varieties of carbonate of lime, because one contains an 

 admixture of gelatinous matter. 



The substances brought together under the name of farinace- 

 ous bodies, are as dissimilar as bodies can be. Among them are 

 gum arabic, wax, horns^ henbane leaves, and eggs. 



Arrangement, however, is a matter of secondary importance, 

 provided the substances when met with are accurately described ; 

 but there are many instances of inaccuracy in Mr. Gray's work, 

 some of which, taken at random, we shall point out, premising, 

 however, that we did not expect to find phosphorus and sulphur 

 among the " Metallic Elements" (p. 84). 



The first error which we shall notice occurs at p. 95 : " Thus 

 oil of vitriol, being composed of three charges of oxygen, united 

 to one of sulphur and ten of water, which last is itself supposed 

 to be composed of a single charge each of oxygen and hydrogen, 

 the compound is expressed thus : 8 + 000+ 10 (H +0); 

 or more concisely, thus, S O^ +. 10 (H O) ; or still more con- 

 cisely, thus, S^ + 10 H^" This passage we have quoted 

 somewhat at length, because it proves incontestably, that Mr. 

 Gray is ignorant of the composition of sulphuric acid ; for he 

 has once in words, and three times by symbols, misstated its 

 nature. It may, perhaps, be requisite to observe, that by the 

 word charge Mr. Gray means what other chemists term atom, 

 proportional or prime ; but oil of vitriol instead of containing ten 

 charges of water, contains only one, as may be seen in any 



