Gurney on Chemical Science, 307 



and nitric acid is said to have uncommon fulminating powers ; and 

 further on, iridium, osmium, rhodium and palladium are repre- 

 sented as probably alloys of other metals, for this satisfactory 

 reason, " since they are found no where but in the ore of plati- 

 num." At p. 220, it is'affirmed, that the muriatic acid of commerce 

 " always contains a portion of corrosive sublimate, which is an 

 oxide of mercury ;" and again, " mercury has a very strong affi- 

 nity for gold, and may be seen to fix itself, and change the colour 

 of this metal, even through the skin and apparel of those persons 

 who have taken it to any extent ; this is a very common case in the 

 West Indies where so much calomel is used ! " 



In the lecture on acids and alcalis, there is a sad nomenclatural 

 jumble at p. 234; and at p. 236, we find, that " what is sold as 

 soda water ought to be simply pure water impregnated with this 

 gas ; but I am afraid this is very seldom the case." So are we. 



Mr. Gurney is very unhappy in assigning to Dr. Priestley the 

 due merits of his discoveries ; he never mentions his name without 

 coupling with it some unaccountable absurdity ; our readers may 

 take the following as a specimen. Speaking of Dr. P.'s experi- 

 ments on the products of fermentation, he says, "the result of 

 that inquiry was, the discovery of carbonic acid, which he called 

 dephlogisticated air. This name was changed afterwards to fixed 

 air, because it is found fixed in almost all vegetable substances." 

 p. 236. Such a cluster of incongruities, it would be difficult to 

 match. 



Nitric acid is stated to be a compound of five to two— five of 

 oxygen to two of nitrogen — five what of oxygen ? two what of 

 nitrogen ? Here our author is evidently floundering amidst volumes 

 and atoms. 



To those who are desirous of a concentrated specimen of 

 Mr. Gurney's eloquence, originality, and scientific acumen, we 

 strenuously recommend the perusal of his twelfth lecture, from 

 which we shall offer a very few extracts only. 



After candidly telling his audience that he is now to occupy 

 their time with conjectures and guesses, about which, he is himself, 

 far from being satisfied or convinced, he observes that he feels no 

 reluctance on this score, having had practice enough in experi- 

 mental philosophy " myself," to know that the most brillian 

 discoveries, and the most important facts and theories, not only 

 may arise out of happy guesses, but that the " most brilliant of 

 these which we boast the possession of, have actually arisen out of 

 those, rather than out of a direct course of study and experiment." 

 Now our limited experience conducts us to a diametrically opposite 

 conclusion, and leads us to infer, that with the sweat of his brow, 

 and the labour of his hands, man must earn his knowledge as well 

 as his subsistence. As to the discoveries of his own, to which 

 Mr. Gurney " himself alludes," we are as yet in dark ignorance, 



X 2 



