214 Reviews, and Notices respecting New Books. 



case of reflection from surfaces, as well as in that of transmis- 

 sion through plates. This, however, I also established, though 

 not without much more trouble than the other, the change of 

 direction of the ray by reflection presenting a troublesome 

 necessity for making the thermometric instrument, that is, 

 the pile, moveable; at least, this was the most unexception- 

 able method. I fully established the fact of comparative non- 

 reflection from a second reflecting plate of mica, the plane of 

 incidence being at right angles to the first; but I had more 

 reason than ever to be satisfied of the value of the simple and 

 effective method of transmission through thin mica-plates. 

 In fact, it was only by the aid of that method that I could 

 have advanced to the still more delicate inquiries which, by 

 the constancy of my first results, I was encouraged to un- 

 dertake. 



[To be continued.] 



XXXVII. Reviews, and Notices respecting New Books. 



The Chemical Catechism, Thirteenth Edition. By the late Samuel 

 Paukes, F.L.S., G.S., W.S., M.R.I., &c. Revised^ and adapted to 

 the present state of Chemical Science, by E. W. Brayley, Jun., 

 A.L.S., of the London Institution. London, 1834. 8vo. pp. xl. 

 and 681 : luith a frontispiece and two other plates. 



FEW elementary works on any branch of science, we believe, have 

 attained a popularity so great or so enduring, as the Chemi- 

 cal Catechism of the late Mr. Parkes. Coeval, in its original publica- 

 tion, with the first great analytical discoveries of Davy, it supplied the 

 public demand for knowledge respecting the phsenomena and objects 

 of Chemistry, which those discoveries had either mainly excited, or if 

 they did not actually excite, had immensely promoted and increased. 

 As the science progressed, displaying fresh wonders to attract the lover 

 of novelty and deeper truths to interest the philosophical student, as 

 well as more and still more important applications to the arts of life, 

 new editions of the Chemical Catechism were prepared by the author 

 to meet the still increasing demand j into which he introduced, from 

 time to time, as they were elicited, the new facts of Chemical disco- 

 very. Between the first appearance of the work in the year 1 806 and 

 the publication of the edition now before us — a space of about twenty- 

 seven years — nearly a thousand copies, upon an average, as we gather 

 from one of the " Advertisements," were disposed of every year. — 

 Ample reasons these for the publication of a new edition, adapted to 

 the existing state of Chemical knowledge. 



The plan of this work is too well known to the public to require 

 particular explanation : suffice it to say that the body of it consists of 

 a popular elementary view of Chemical Science, delivered in the cate- 

 chetical form, to which are attached numerous illustrative notes, giv- 



