VOL.2, NO. 9
RECENT BOOKS
chapters have been omitted." This cditirm retains the man" commendable features of the first edition and adds t o them, as well as bringing the subject-matter up-to-date. Among the many points of excellence may be noted the paragraphs on feed water treatment, on the setting of Portland cement and on electro1ysi.. An extended treatment of types of alloys together with an uotaurlly d e a r introduction t o the use of "freezing point" diegrams preceder a "uy extensive presentation of non-ferrour alloys and of the metallomaphy of iron aod steel. The excellent chapter on hydrometry reappears in nearly its original form. Partoo many men hiehlv versed in chemistrv have no conceotion of the rignifieanee of the B a u d scales! A few minor mir-statemmt. and omi~sions have been noted and there, strangely enough, have persisted from the earlier edition. Rutile (p. 93) is a far more usual mineral than either braakite or snatase, and one wonders why the author writes its formvla TirO.. The we1 9rorrrr is much "red for making Portland cement from materials mher than marl (p. 313). and n o mention is made of titanium whit?= under white paint pigments (P. 349). The chapters on primary and secondary cells could be further strenxthened b v a more eonsisfcnt treatment of the nature and charge of the electric current. After an excellent treatment of primary cells in terms of electrons (p. 477) and a very lucid presentation of the relationship between the Bow of electrons and what has been arbitrarily chosen ru the "direction of the eurrent," it seem regrettable t h a t the author should offer an explanation of the action of the lead accumulator in terms of poritive electricity (p. 497). The setion of the Edison cell ir well explained i n term of unitr of negative electricity (p. 508) instead of in both unitr ar in t h e erst edition. I t is certainly better to nay t h a t "hydrogen ions will discharge" (p. 479). rather than "hydrogen ions separate out" (p. 4861, when direusingthechangeofhydrogcnionrtofreehydroe n . The points just cited d o not, however. detract ap~reeiablyfrom the general worth of t h e book. I t should be in the library of every enginewho desire. t o know somethioe about the materials of h b profession. Tbis book cannot be too highly recommended for students of engiacering. Teachers of ~ e n e r a chemistry l will find i t a very valuable aid. The reviewer knows no better single source for the sort of information designed t o interest boys in chemistry. The book should be on the desk of every high-school teacher of rhemirtry. R. E. Kma ~~~
.
-.
~
~
-
Noa-Metallie Minerals, OccrrrrmceReparationRAYMOND E. L ~ o o o , General Utilization. Manager, Southern Minerals Corporation; Tcehoiesl Director. Eastern Magnesia Tale. Co.. Ine. McGraw-Hill Book Co.. Ine., New York, First Edition (1925). viii 6S6 pp. 51 figures. 15.25 X 23.5 cm. $6.00 net.
+
819
I n this volume the writer hsr covered in a general way t h e technology of the no"-metallic minerals. The material is grouped under the usud trade headings and these are arranged alphabetically. A liberal "re has been made of cross references. Under each genersl heading the author discusses minerals and compositions. general description, physics1 properties, geologic occurrence, geographic distribution, production and eonrumptioo, mining hnd milling, marketing and shipping, specifications and terte, and utilization. Many now sheets of praenaer are given and tables of pmduction, consumption, and price. are numerous. "The non-metallic mineral field, a~ covered by thil book, includes primarily those minerals of industrial importance which are mined industrially for use other than ass s o u r c e d the metals. certain minerals, such as bauxite, have both metallic and noo-metallic applications and in there eases only the non-metallic mineral phases are covered The field is also limited by omitting those minerals of organic origin used primarily as fuels. and also the natural biturnin. and hydmearbons. . Selected bibliographies follow each subject heading, They ref- t o t h e best treatises on t h a t subject and include references t o complete bibliographies. This book repre=ents arather critical survey ofa considerable amount of information hitherto available only in diverse and widely separated publications, many of which were difficult of access for the average person interested in the technolwy of some non-metallie mineral. The author has attempted a very di6iedt task and has achieved p considerable degree of success therein. The book seems t o meet a very definite need in technological literature. This publication should serve as a ready reference book for the teacher of ehemirtry who is always being asked, " m a t is i t used for)" From Abrasives to Zirconium Minerals the h w k is a real rtorehoune of information and reference. R. E. Klaa
. .. .. . . . . . . . ."
OTHER PUBLICATIONS RECEIVED Laboratory Qnestionaaire; The Laboratory. This is the report of the result. of an investigation undertaken by the New Emgland Assoeiatioo of Chemistry Teachers in commemoration of twenty-five yeof work dvring which marked changes in t h e methods of teaching chemistry have takcn place. Published in the Report of the Twenty-fifth Meeting of the N. E. A. C. T.. in part, and completed in a Supplementary Report. Price fifty cents. A questiornaire, sent to over one hundred teachers of chemistry in the secondary ~ e h o o l s and colleges of New England, covers the subject of the what and the why of the laboratory teaehins of chemistry. The persons to whom this questionnaire was sent were selected very care-
