Reviews—Determinative Mineralogy. 179 
and Penfield’s bulky Manual and Rutley’s Elements of Mineralogy, 
one wonders why the smaller book should have been compiled at all. 
Certainly it only claims to deal with analysis, but analysis alone is 
generally a cumbersome and sometimes an insufficient means of 
determining minerals. Asa supplement to the many excellent books 
on determinative mineralogy which already deal with blowpipe 
analysis (such, for example, as those noticed below) this little 
handbook can claim at best only a very limited field. Unnecessary 
space is devoted to wet methods of analysis, and this might have 
been better occupied by lists of minerals with their composition and 
simpler properties. Microcosmic salt is said to be commonly termed 
‘micro’; sodium carbonate is referred to as ‘soda’; the use of the 
scale of hardness is mentioned, though the scale itself is not given. 
IJ1.—Dererminative Mrneratocy. ByJ.V. Lewis. Wiley & Sons. 
2nd ed., revised. pp. 155. 1915. Price 6s. 6d. net. 
‘P\HIS edition differs from the first in no essential particulars, but. 
it is improved by the addition of several new features that 
greatly enhance its usefulness. A number of delicate tests have been 
introduced for various elements or minerals, and the determinative 
tables have been made more complete. The only blemish that 
disfigures the pages of the book consists in the use of a large number 
of abbreviations, many of which are not only ugly but, if saving of 
space was the ideal sought after, quite unnecessary. The index is 
good, and the references to any mineral can be located with ease. 
IV.—Etements or Mineratoey. By Franx Rouriey; revised by 
H. H. Reap ; introduction by G. T. Hottoway. Murby & Co. 
19thed. pp. 394. 1916. Price 3s. 6d. net. 
UTLEY’S well-known book has long been a favourite; among 
students for its cheapness, among teachers for its thoroughness 
‘and general accuracy, and among prospectors for its completeness and 
convenient size. If this was true of the old ‘ Rutley’, then the 
present revised and largely rewritten edition ought to enjoy a still 
higher degree of popularity. Not only is the work brought com- 
pletely up to date, but the presentation of the facts and the aspect of 
each printed page is much more attractive than formerly. The 
inclusion of a chapter on optical properties and its application to the 
determination of the silicate minerals will be much appreciated. 
The economic side of mineralogy is given considerable prominence, 
and attention is directed to the mode of occurrence and uses of 
minerals rather than to localities alone. The arrangement of minerals 
according to their most noteworthy element has many advantages, 
especially from the point of view of determination and economics. 
In each case an introduction to the element in question is provided, 
including a list of the chief minerals into which it enters. The book 
concludes with a useful glossary, a table of the geological systems, 
and a very complete index. MReviser and publisher are alike to be 
congratulated on their success in building on the sound foundation of 
Rutley a most valuable and comprehensive work. 
