NEW BOOK§ est to the laboratory worker, and he has succeeded admirably. The reviewer regards this as the most useful book on the subject that he has yet read. Progress in Nuclear Energy. Series IX, Analytical Chemisfry. V d . 5. instrument a n d Chemicai Analysis Aspect5 of Electron Mi'croanalysis a n d Macroanalysis.
Herbert A . Elion. ix + 256 pages. Pergainon Press, Inc. 44-01, 2lst St., Long Island City, N . Y . 11101. 1966. $14.
Reciewed b y L . S. Birks, U . s. Naval Research Laboratory, Washington, D , C . 20390. I t is only about 15 years since the beginning of elect'ron probe ana,lysis but' the subject, has attmcted grea,t att'ention because of the instrument's unique ability to perform quant'itative chemical analyzis on seleckd, micron-sized local areas in alloys, minerals, biologicak, etc. Many papers a n d several books have been published outlining principles and practice. The most re-
Yes, our
DESCRIPTION: SARGENT,MODEL MR RECORDER-automatic, self-balancing, 10-inch potent ornet& recorder. H'gh ga'n anip 'fier; h.gn sta2 :I s31i3 state refereice power s..pp'y needs no staodarddar:on. L m operated.
QUANTITY RECORDED: mV, V, i r a and ma-selected by panel switch. ZERO DISPLACEMENT: calibrated ranges of 10, 100, 1000 and 5000 of the selected units, upscale or downscale.
ELECTRICAL RANGE: twelve pre-calibrated ranges by switch selection-0.5, 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000. Variable range expansion from 100% (off) to 40% of selected range.
LIMIT OF ERROR: 0.1% or ~ Y V , whichever is greater. SOURCE RESISTANCE TOLERANCE: 50,000 ohms in most sensitive range, increasing with increasing range.
ELECTRlCAL FILTERING: four position switch t a reject transverse and common mode A.C. superimposed on the D.C. signal, without loss of sharp balancing characteristics.
DAMPING GAIN ADJUSTMENT: automatic with range change; panel dial for fine adjustment -especia!ly for low resistance systems like thermocouples.
CHART DRIVE: twelve synchronous speeds-0.5, 1, 2, 4, 10, 20-by dial select!on, inches per hour or per minute by panel switch. Rapid scanning in forward and reverse.
PEN SPEED: 1 second for f u l l scale transverse. CHART TAKE-UP: automatic, by motor with preset torque-of by-pass for free end chart tear off.
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This gives you some idea why the SARGENF MODEL MR can do the work of- S less versatile recorders, manual potentiometers or precision meters. To get the complete picture, write for Bulletin MR.
NT@ SCIENTIFIC LABORATORY INS1RUMENTS.APPARATUS. E. H. S A R G E N T & 60. 4647 W e s t Foster A v e n u e Chlcaga, Illinois 60630
74 A
a
CHEMICALS
Chicago Anaheim, Calif. B i r m i n g h a m e C i n c i n n a t i Cleveland Dalias o D e n v e r Detroit Springfield, N.J. D Toronto, Canada Circle No. 141 on Readers' Service Card
ANALYTICAL CHEMISTRY
cent of these is the book by H. A. Elion. The book starts with an introductory chapter on $istorical background which emphasizes the roles of the corporations with which the author has been connected. This is followed by chapters on electron optics, x-ray crystal optics, detectors, specimen preparation, factors in quantitative analysis, and miscellaiieous related topics. Chapter headings notwithstanding the reader finds that the book is clearly divided into two distinct areas, namely a detailed dispqsion of electron optics which takes u p 30% of the book followed by a general, descriptive coverage of the rest of the subject. TYithin the area ofLelectronoptics, D r . Elion takes. a somewhat low position on the merits of afocal electron lenses but unfortunately does not give any quantitative 1-alues for their aberrations compared with usual electron lenses. Other researchers more versed in electron optics than this reviewer have stated in the past that the theoretical ad\-antages ascribed by Elion to afocal lenses do not exi-t in practice. In addition, most analysts have n o control over the electron optips design of instruments : thus the lengthly discussion is largely wasted on them. Contrasted n i t h the overly long section on electron optics, many of the topics on which the analyst, especially the relative newomer, needs specific guidance, are covered in a very cursory fashion or only by references to the literature. For instance, there is no discussion on precision or accuracy (they are not even listed in the index) : there are only three sentences on the important shift of pulse amplitude x i t h counting rate for proportional detectors : procedures for converting meaeured x-ray intensity t o chemical composition (quantitative aiialysis) are discussed so briefly that the analyst has no equations t o actual13 use. In favor of the book, it should be said that, except for the electron optic,c 2.ection, the material is very readable. Also the bibliography is extensive and seems quite complete. Chemical Principles in Calculations of Ionic Equilibria. E n d J . A l a r -
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golis. zi 482 pages. The ~Tfacnaillan Co., 60 Fifth Ave., iYew Y o r k , N.Y . 10011. 1966. $7.95. ( P a p e r back : 83.95).
Reviewed by Richard A. Durst, Department of Chemistry, Boston College, Chestnut Hill, Mass. 02167. The material presented in this text is n-ithout doubt very important in the ouwall education of a chemist, but unfortunately has been relegated in recent
