1224 Journal of Applied Microscopy 



employed, unquestionably produce certain changes in the milk and cream which 

 detract somewhat from their value. The question whether pasteurization at a 

 lower temperature of G0° C (140° F) is not sufficient to kill the tubercle bacilli 

 has been investigated by several observers. The authors of this paper have 

 tested this subject more carefully than others up to the present time, and they 

 reach the extremely important conclusion that an exposure of tuberculous milk 

 in a tightly closed pasteurizer for ten minutes to a temperature of 60° C destroys 

 the pathogenic character of the tubercle bacilli that are present. When, how- 

 ever, the milk is exposed under conditions that enable a scum to form on the sur- 

 face, the organism resists this temperature for a longer time. The authors, how- 

 ever, regard a pasteurization of milk at 60° C, for not less than 20 minutes, under 

 conditions that prevent formation of a scum, entirely sufficient to destroy the 

 pathogenic character of the tubercle bacilli present. 



The author finds in a case of chronic pulmonary gangrene a species of bacil- 

 lus which, in its microscopic appearance and in its staining properties, agrees 

 with the tubercle bacillus. Its culture relations on various media are, however, 

 different from those of the tubercle bacillus. For example, in glycerin agar it 

 produces an intense orange yellow pigment. It is not pathogenic for guinea pigs 

 and seems to be identical with one previously isolated by the author from butter. 



This last article describes the characters of a tubercle-like bacillus, found in 

 butter. The chief characteristic of this organism is that it will not grow in gela- 

 tin stab cultures at an ordinary room temperature. In this respect, as well as in 

 the fact that it cannot be adapted to room temperatures, it agrees with the tuber- 

 cle bacillus. For mice and birds the organism is not pathogenic, but for guinea 

 pigs and rats it produces an infection which cannot be distinguished from true 

 tuberculosis. The author believes that this organism, though not the typical 

 tubercle bacillus, is a closely related variety. h. w. c. 



NOTES ON RECENT MINERALOGICAL 

 LITERATURE. 



Alfred J. Moses and Lea McI. Luquer. 



Books and reprints for review should be sent to Alfred J. Moses, Columbia University, 



New York. N. Y. 



Ternler, P. Nouvelle contribution a I'etude The crystals were obtained by distilla- 

 cristallographique du cadmium et du zinc ^[q^ of ^heir metals in a vacuum at low 

 metalliques. Bull. Soc. Min. 23: 18,1900. 



temperatures. 



Zinc crystals were very small (less than 1 mm. diam.), quite clear and in hexa- 

 gonal tablets, with periphery formed of rhombohedral facettes. c = 1.356. 

 Nine forms noted. 



Cadmium crystals showed a marked similarity to those of zinc, with c = 

 1.335; the zinc crystals, however, sometimes showed two prisms. Seven forms 

 noted. 



