13 JUNE 1891, Page 22

Manual of Assaying : Heinemann's Scientific Handbooks, By W. L.

Brown and A. B. Griffiths. (Heinernann.)—This is certainly a practical book, for, besides the laboratory assays and analysis, there are some of the more expeditious assays which can be applied on the spot to ores by a person of ordinary intelligence, and are accurate enough for a minor to draw one of the two con- clusions with which he alone concerns himself. Gold, silver, lead, copper, and fuel only are treated of in this manual, and for them alone is it necessary to make a hasty analysis ; and the man who,

without resources, can speedily improvise an assay, is in great demand in unexplored mining countries. This will be a useful reference-book to many people, and if they cannot agree as to the reliability of the methods, there are plenty of hints and some good advice to be found in it.