RECENT BOOKS WAYE-LBNDTH TABLES. Measured and compiled under the direction of G. R. Harrison, by staff members of the spectroscopy laboratory of the Massachusetts Institute of Technology, assisted by the Works Progress Administration. The Technology Press, Massachusetts Institute of Technology, and John Wiley and Sons, Inc., New York City, 1939. xxviii f 429pp. 19 X 28 cm. $15.00. This book is prohably the most valuable contribution of recent years in the field of spectrochemica1 analysis. The widespread use of quartz Littrow spectrographs has given the analyst sufficient dispersion for photographing rather complex spectra whose analysis has a t times been diilicult because of lack of adequate wave-length tables. The advantages of the new tables are more accurate listings of wavelengths and an expanded intensity scale, which will greatly facilitate the identification of faint lines and enable the analyst better t o judge of the presence of possible interfering lines. I n the M. I. T. TABLES,as this book is already universally known, there are 109,275entries, including 1381band heads which frequently appear on spectrograms. Intensities are given for the arc, spark, and discharge tube. The intensity scale, customarily given for a range of 1-10, has been expanded to a range of 1-
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9000. Twenty-five different ratings are given in this range. The new intensity scale more nearly reproduces the appearance of lines as observed on a plate, and is one of the most valuable features of the book. The spectra of eighty-seven elements are given, for the wavelength range 10,000 t o 2000 A. The lines listed, while hut s fraction of the total number of lines reported in this wave-length region, account foe same ninety-nine per cent. of the radiation. With a few exceptions all lines having an intensity of 2 or more are listed. When term values are known the spectra of neutral and sin& - , ionized atoms are desimated hv the numerals I and 11, as in other wave-lrngth table;. Spectra arc not included for atoms in hizher scater of ionization. A very vslunbk f:ature of the table is the reference citation with each item. I n addition to the main table there are short tables giving (a) the number of lines listed for each element, (b) sensitive lines arranged by wave-length, and (c) sensitive lines arranged by elements and classified according to the order of sensitivity. These brief tables of sensitive lines are very valuable for analysis. since the presence or absence of an element can readily be determined from the relative intensities of a few lines. The reviewer, for one, would welcome the reprinting of these two tables
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WHAT H E MUST KNOW SCIENCE
SAPETY PRECAUTIONS
Vapor phase e~rrrification Disullariun of binnrv and tcrnarv mixture Economic significanfe of esters, especially duco, rayon acele, soaps, and so forth, also nitro glycerine, nitr, cellulose, and so forth Grienard reaction ~chGtten-Baumanreaction (See bases, salts, and so forth) Alkaline fission Agents Catalysts Yapor phnse hydrolyses L c ~ t h e rnmnufacture Phenol nnd nnntholj Enzymes and their uses
When operation is economically satisfactory
Frequent testing of equipment
Basic reactions, prodncts, by-products, economic sig. nficance Constructive and disruptive a c t of anhydrons aluminum chloride Chemical factors Scholl and Fries reactions Rine closures
Nhen operation is economicaUy satisfactory
Frequent testing of equipment
Economic value of polymers Gasoline from cracking still gases Vinylacetylenes and "Duprene" from acetylene Catalvsts Basictheory and reactions By-products Recovery Synthetic resin type reactions Pronerties Glfptals Bakelite Vinyl resins Furfural
&%en operation is economically satisfactory
