Scienti/ic Reviews. 267 



Mr. M'Vicar has a high reverence for antiquity. He admires 

 Plato, because he threw out the conjecture shown in the book 

 before us to be true, (!) that the form of flame is a pyramid. He 

 quotes Boyle as an admirable man, on account of his chemical re- 

 sults ; and Boerhaave has no small share of his adoration. He la- 

 ments the disuse of old names too. " It is to be regretted," he 

 says, " that the names given by the fathers of the science are so 

 completely forgotten ; for it is not right, without some good excuse, 

 to change a name which has been given by any one to the substance 

 he has discovered or first described." Kind, good soul ! And there- 

 fore we find him talking of calx, and argil, and vitriolate of iron, 

 and ferrane, and phosphorane ; and therefore, no doubt, he hopes 

 that when his new carbonic gases are discovered, they will be call- 

 ed citrogen and pyragynic acid. We cannot, of course, compel 

 other chemists to adopt a particular nomenclature, but should it be 

 our own lot to fall in with these two non-descript gases of Mr. 

 M'Vicar's, we shall certainly so christen them. 



One meets with little passages now and then in the course of the 

 ^ork, at which one cannot help smiling. Speaking of the forma- 

 tion of bodies from their ultimate elements, the author quotes the 

 texperiment of Sir H. Davy, in which, during the decomposition of 

 water by the galvanic battery, in an agate vessel, he obtained not- 

 able quantities of soda, and adds, 



" He satisfied himself, however, that it was derived from no other source than 

 the cup, because he did not obtain any, when the water was acted on in gold ves- 

 sels. But the silica of the agate has a great affinity for soda, and would dispose 

 to its evolution according to well known and acknowledged principles, while gold 

 has no such affinity. Hence, though soda was not developed in the gold, it does 

 not follow that it was not developed in the agate." P. 240. 



And in page 312, he says, 



•' Spirit of salt, or oil of vitriol, united to ammonia, may be handled without 

 the fingers suBeiing, and this we ascribe to the circumstance, that the acid is neu- 

 Iralized by the alkali. But if our fingers, like those of a calcined statue, hap- 

 pened to be made of lime, we might almost as well handle spirit of salt as sal 

 ammoniac ; and it would be true, that, in as far as our sensations were concern- 

 ed, the acid united to the sal ammoniac was as little neutralized, as with our pre- 

 sent fingers we find it to be vhen it is united to water." 



But we must bring our remarks to a close, adverting first to two 

 errors in matters of fact which we have happened to meet with. 

 All the experiments hitherto made, tend to show that ammonium, 

 or that compound of azote which forms an amalgam with mercury, 

 consists of one atom azote and four atoms hydrogen. Mr. ]\f 'V. 

 (p. 309.) takes away hydrogen from his ammonia, in building the 

 form of his ammonium, " and makes it to consist of one azote to two 

 of hydrogen. 



In page 465, he says, 



" Crude or cast-iron, in the solid state, possesses rather a less volume than in 

 the liquid state ; but solid cast-iron floats on liquid cast-iron like wood upon wa- 

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