252 Notices respecting New Books, 



even a higher temperature than that of coal-gas ; they also 

 possess the advantage of yielding pure and innocuous combus- 

 tion products — water and carbonic anhydride. They can 

 therefore be employed without danger in the vicinity of deli- 

 cate instruments, which would be otherwise injured by the 

 acid combustion-products of our impure gas supplies. All 

 who are in the habit of using platinum vessels are aware of 

 the injurious effect produced upon their surfaces submitted to 

 the action of the flame of impure gas : with the use of these 

 flames this effect is obviated, and delicate platinum surfaces 

 and instruments can be heated or cleansed in them without 

 injury. 



Experiments made to determine the cost for the supply of 

 an ordinary Bunsen-flame gave the consumption of common 

 ether about 1*5 ounce per hour, the cost of which is about two 

 pence ; with common benzoline the consumption was at the 

 rate of one ounce per hour, or under one farthing. 



In tropical climates, such as that of India, where the great 

 volatility of ether or benzoline would be unfavourable to their 

 use, they might be replaced by naphtha or common alcohol. 

 Filling the vaporizing-cylinder with naphtha and immersing 

 in water at about 120° F., an intensely hot flame was main- 

 tained from the resulting vapour. With alcohol the same 

 result followed when immersed in water at about 130° F. In 

 those countries where the operator is deprived of the use of 

 coal-gas this method for obtaining a supply of heat could be 

 used with advantage. 



The experiments were made in the laboratory of the Royal 

 College of Science, under Professor Galloway. 



XXIX. Notices respecting New Books. 



The Art of Scientific Discovery, cr the general conditions and 

 methods of research in Physics and Chemistry. By Gr. Gore, 

 LL.D., F.B.S. London : Longmans, Green, and Co. 1878. 

 (Crown 8vo, pp. 648.) 

 r pHLS is the work of a well-known chemist, of one who has 

 •*■ practised the art of discovery, and who might be expected to 

 discourse well on an art in which he has obtained a certain measure 

 of distinction. Xor is the book by any means devoid of interest ; 

 indeed, a partial reviewer might easily point to many well written 

 and instructive passages, he might allege that the book is a store- 

 house of facts, that its contents show not only that the author is 

 well acquainted with some branches of science, but also that he 

 has read the history and at least paid attention to the philosophy 

 of science. And yet, while recognizing the truth of all this, we 

 must confess that we have read the book with great disappointment ; 

 it seems to us to raise expectations which it by no means fulfils, 



