1823.] Mr, Gray's Elements of Pharmacy, 46$ 



iodine, and the hydriodic acid of hydrogen and iodine ; it is the 

 latter only which is formed, excepting a quantity of phosphorous 

 acid, of which no notice is taken, nor is the decomposition of he 

 water even hinted at, although the formation of the hydriodic 

 acid depends upon it (p. 166). 



The directions for detecting the presence of arsenious acid 

 (p. 151) are thus given in eight lines : — " If a person is suspected 

 to be poisoned with arsenic, the antidote that is most readily 

 obtained is a solution of soap ; and the contents of the stomach 

 may, to obtain satisfaction, be dissolved in boihng distilled 

 water, the solution strained, and then, if any white arsenic has 

 been taken up, on the surface being touched with a stick of 

 lunar caustic, a sulphur-yellow precipitate will fall down imme- 

 diately from the place touched." These directions are incor- 

 rect, and totally inefficient ; for it is necessary to make use of 

 solution of an alkali, either carbonate of potash as proposed by 

 Mr. Hume, or ammonia as preferred by Dr. Marcet. Besides this 

 omission, Mr. G.has not stated one word of the ambiguity which 

 may arise from the presence of a phosphoric salt, nor does he 

 give any directions for procuring the confirmatory evidence 

 which may be obtained by the use of sulphuretted hydrogen, 

 sulphate of copper, or from the alliaceous smell ; nor is the direct 

 evidence afforded by iiietallization in any way alluded to. 



We cannot help noticing the contemptuous and unwarrant- 

 able language which Mr. Gray employs when speaking of La- 

 voisier, a philosopher to whom every one, but Mr. Gray, knows 

 that science is deeply indebted, and whose misfortunes entitle 

 his memory to respect. " Lavoisier reversed the analogy, and 

 instead of continuing to identify the metallic oxides with the 

 earths, compared the earths to the metallic oxides ; and, being 

 a Frenchman, he of course claimed this mere shifting of the 

 terms of the analogy, as a great discovery." 



With one more quotation, we shall conclude our notice of the 

 Elements of Pharmacy. In page 88, some of the properties of 

 azote, chlorine, and iodine, are mentioned, and then come the 

 following observations : *^ All of these are esteemed by Sir H. 

 .Davy, Brande, and the chemists of that school, as simple bodies 

 in the present state of our knowledge, but Berzelius and the 

 rationalists consider them as oxides ; the supposed bases of the 

 two first being called by him nitricum, muriaticum, and that 

 of the third may be distinguished by the name of iodium." Thus 

 we have an author who has four times misstated the composition 

 of sulphuric acid, venturing to divide chemists into the two 

 classes of the rationahsts and irrationalists, and placing among 

 the latter the inventor of the safety lamp. — Edit, 



