This is n soiiic\vhat uiiusunl but most oscful hook. Dr. Xcwinnn, who contrihutcs n foreword, says that, it sliould coniniciicl itsolf to n widc ficld of tcnclicrs of scicncc. Witli tliiit coiiiinciidatioii wc licnrtily agrce nnd would ndd to tlic widc ficld nll tliopc \*I10 arc conccriicd in tlic cnrc :ind ni:iiritciiriiicc of ti clicinietil or physical laboratory. Wc hive tested i t by takiiig it into prncticnl use in tlic laborntory and find it t o be full of uscfiil iiiforiiintion, recipes mid instructions in coniicction \vit,li tlic iiinintcnniicc of ti hborntory. It gives niucli help on thc geiiernl ciire of instruments, on rcpiiirs, the construct,ion of new or spccinl nppnratus, mid 011 all inntters connected with cciiiciits, solvciits, glnss-blowing, grnduatioii of npp:iratus. Tlicrc nrc, too, uscful cliaptcrs on elcctric motors, clectricnl iiie:isiirciiiciits, clcctropliitiiig, soltlcriiig, tlic plntiiig of mirrors, lniitcrii slides, niitl accuiiiulil tors.
Thc book bcnrs the iiinrk of the ~)r;ictienl iind cspcriciiccd Inlortitory \vorker nntl tlic iiistructioiis givcii will ciiablc 11 clicmist to construct his o w spccinl rrpparntus wit11 iiicrcnscd cflicicncy. Its purcliasc will IN likely to effect, n sitviiig ninny times greittcr tliiiii its cost.
LE. E.
C. SCIEXTIVIC ESCYCLOPISI)IA. l3y I>. Yrtn Nostrand nnd others. Pp. 123.1. London : Cliapmnu k Ha& Ltd., 1938. 50s.
This is very ncarly a inodcl of whnt t i short scientific encycloptcdin slioeld be. T t ilcnls with thc scicnccs of aeronautics, nstronomy, botnny, chemistry, cngiiiccring, gcology, mntlicmntics, mcdicinc, mincrnlogy, navigation, physics, nnd zoology. 11s the book is, for un cncyclopadio, short, and ns cncli hending is ndcquatcly treated, it follows thiit i t is not very inclusivc rind ninny of the less important words mid siibjcets nrc not to be found.