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XLVIII. Notices respecting New Books. 



The Laboratory Guide for Students of Agricultural Chemistry. Ar- 

 ranged by Arthur Herbert Church, M.A., Professor of Che- 

 mistry in the lloyal Agricultural College, Cirencester. Post 8vo. 

 London : Van Voorst. 1864. Pp. viii and 94. 



THIS little work is divided into two Parts. The first, intended 

 as an outline of the general course of qualitative analysis, 

 begins with an enumeration and brief description of the more com- 

 monly occurring elements ; then follow concise directions for pre- 

 paring and purifying the reagents required in the subsequent pro- 

 cesses ; and next about twenty-three pages devoted to " The Method 

 of Analysis." The second Part consists of a series of examples for 

 practice in quantitative analysis, selected from among such sub- 

 stances as are most likely to come in the way of an agricultural 

 chemist. 



It is this second part which gives to the book its distinctive cha- 

 racter and its chief value. The examples here given have been judi- 

 ciously selected so as to embrace a considerable variety of processes, 

 while the working directions are almost always clear and sufficient 

 for the object in view. A few of the best volumetric methods have 

 been included, among which are two very good ones that we do not 

 remember to have frequently met with in works of this class — namely, 

 Mohr's process for the estimation of chlorine by nitrate of silver and 

 chromate of potash, and the late Dr. Pugh's method of estimating 

 nitric acid. This portion of the work appears to us so well planned 

 and so likely to be useful, that we should be glad to see it extended 

 so as to occupy the whole book instead of the last fifty-three pages 

 merely. On the other hand, we do not think that the consequent 

 exclusion of the part devoted to qualitative analysis would greatly 

 diminish the value of the work. As it is, Professor Church leaves 

 so much, of what it is necessary for the student to know respecting 

 this branch of the subject, to be supplied from other sources, that 

 he might, without much danger, have left the whole of what is 

 given in this portion of his book to be supplied in the same way. 

 Indeed, were this a suitable occasion for discussing the question, 

 very much might be said against that system of laboratory teaching 

 in which a " Scheme " or " Method " of qualitative analysis, such 

 as that contained in the first part of this work, is put into the hands 

 of the student at the very beginning of his course. We believe that 

 the very opposite system to this would, more than anything else, 

 tend to promote the rational study of chemistry. As far as possible, 

 we would have students encouraged to rely upon their own experi- 

 ence and observations rather than upon books of any sort ; and 

 most of all we would endeavour to persuade them to use no Analy- 

 tical Schemes or Tables until they can construct them from their own 

 knowledge, or are independent of them altogether. Mr. Church's 

 work, however, not being addressed to students of scientific che- 

 mistry, so much as to those whose object is merely to become ac- 

 quainted with one of its most important practical applications, and 



