382 Notices of Books. [July, 



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doubt turn up unexpectedly in many minerals. In this work 

 equal prominence is given both to the rare and to the ordinary 

 elements. 



The order in which the analytical separation of the metals is 

 carried out will be readily understood. Take, for instance, the 

 case of copper. After giving the best method for the detection 

 and quantitative estimation of this metal, comes a description of 

 the processes for separating it from those metals which have 

 been previously passed under review, as mercury, silver, and 

 zinc ; but no attention is paid to the separation of copper from 

 such metals as lead, tin, &c, which have not previously been 

 treated of. Under the respective headings " Lead" and " Tin," 

 the separation of these metals from copper is described. 



A complete list of separations has not been attempted. Where 

 no process of separation or estimation is given, it may be 

 inferred that the author has had no experience in any but the 

 well-known methods employed in most laboratories ; and to have 

 introduced these ordinary processes into the work simply for the 

 sake of filling up gaps would have largely increased its bulk 

 without adding materially to its value. To save space, the 

 description of a process is frequently discontinued at the point 

 where the substances under separation are brought to such a 

 state that the concluding steps are obvious. 



No special system of weights and measures has been em- 

 ployed ; many of the descriptions having been condensed from 

 the original memoirs, it was thought better to retain the system 

 therein adopted, so as to have simple numbers to deal with, 

 instead of having to convert them to one common scale and to 

 introduce decimals ; thus — when an author says take 8 grains of 

 a substance, 0*51816 gramme has not been substituted; and 

 where 10 grammes are mentioned, he has not put 1543840 

 grains. When not otherwise expressed, all degrees are accord- 

 ing to the centigrade scale. Formulae have been avoided as far 

 as practicable. 



A Series of Chemical Problems, for use in Colleges and Schools ; 

 adapted for the Preparation of Students for the Government 

 Science and Society of Arts Examinations. By T. E. 

 Thorpe, Ph.D., Professor of Chemistry in Anderson's 

 University, Glasgow. With a Preface by Professor 

 Roscoe, B.A., Ph.D., F.R.S. London : Macmillan and Co. 

 Manchester: James Gait and Co., 1870. 



In a short preface to this little book, Dr. Roscoe says that 

 it will prove a great boon to those engaged either in teaching or 

 in learning the science ; and on going over the contents we per- 

 ceive that the questions have been prepared with great skill, and 



