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The literature contains numerous references (5) which pertain to the treatment of steroids with sulfuric acid, either alone or in combination with other reagents. The chromogens so developed were used for purpose of identification or estimation. Special reference is made to the recent noteworthy work of Zaffaroni and coworkers (1 m, n), who have determined the spectra of a number of steroids in concentrated sulfuric acid. Only a relatively small number of compounds, limited in variety of structural features, were examined. Certain aspects such as concentration studies, structural relationships, and the like were not discussed. In view of Zaffaroni's work, and our own experience which indicated that in concentrated sulfuric acid hydrocortisone and its epimer, 11-epi-hydrocortisone, were easily distinguishable (2), we decided to explore 1146 SUMMARYThe absorption spectra (220-600 mg) of 220 steroids in 97% sulfuric acid at 25°have been determined after allowing the solutions to stand for 2 hours T h i s c o n t e n t i s

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The recoil-free coherent resonant scattering of the 14.4-keV Fe 67 gamma rays has been investigated by employing the techniques of the Mossbauer effect together with those of total reflection. Of particular interest are the observed large interference effects attributed to the coherent superposition of the several resonant nuclear contributions and the nonresonant electronic contribution to the scattering amplitude in the forward direction. Gamma rays from a 300-mCi Co 57 source, diffused into the thin edge of a stainless steel plate, were reflected at small glancing angle 0 by an optically flat Fe 67 mirror through a narrow slit into a Nal scintillation detector. The resonant frequency spectrum of the Fe 67 nuclei in the mirror was scanned by varying the source velocity v. Values of the absolute reflectivity R (0,v) were obtained by comparison of the direct and reflected measured intensities. In an auxiliary experiment R(v) was measured with an external magnetic field applied to the mirror. The results of these measurements were compared with computerprogrammed calculations based on the classical optical theory of total reflection. Appropriately averaged quantum-mechanical expressions were introduced for the coherent resonant nuclear scattering amplitude in the forward direction. Separate computations were made for each polarization state of the incident radiation; these were averaged to give R(9,v) appropriate for an unpolarized source and a polarizationinsensitive detector. Suitable integrations were performed to take into account the frequency spread and angular width of the incident radiation. For 0 = 4 mrad, R(v), computed with the six resonances of normal ferromagnetic Fe 57 , agreed in shape and magnitude with the observed reflectivity, when the resonance width was assumed to be four times the natural width. For 0 -2 mrad, where the gamma-ray penetration depth is small, anomalies in the magnetic and chemical environment of the Fe 67 nuclei near the mirror surface required the introduction of additional resonances for FeO and for nonmagnetic Fe.