Freud, Sigmund. the Problem of Anxiety. Translated Koerth. Controlling Human Behavior. Pp. Xiv + 638. 57 Figures. Macmillan. $2.90. Strain, Frances B. Being Born; a Book of Facts For

corresponding to most of these ammonium salts have also been studied in aqueous solution, and many new Raman lines in addition to those previously recognized4 have been found. The detailed discussion of these spectra is necessarily somewhat complex and will be presented elsewhere, but one significant point may be reported here. Free primary and secondary amines give one (or two) powerful Raman lines between 3,300 and 3,400 cm-', presumably associated with the un-ionized N-H linkage; the corresponding ammonium salts, however, in which the amino group has acquired a proton, show no Raman frequencies above 3,050 cm.-' Likewise the sodium salts of glycine and alanine show strong lines near 3,330; the isoelectric amino acids show no lines above 3,030. The conclusion follows that the amino group in glycine and alanine must be electrically charged; in other words, that these amino acids exist as dipolar ions at the isoelectric point. This supplements the earlier spectroscopic proof of this structure,5 based on studies of the ionization of the carboxyl group. Ample evidence for the theory of dipolar ions has been forthcoming from other sources, but the evidence from Raman spectra is valuable for the elarity and directness of the proof it offers for the validity of this structure. This method also should be directly applicable to the determination of structure in new compounds containing these ionizable groups.