84 PETROLOGICAL ABSTRACTS AND REVIEWS 
LoEWINSON-LESSING, F. ‘‘Ueber die chemische Natur der Felds- 
path amphibolite, Annales de Institute Polytechnique Pierre le 
Grand a St. Pétersbourg, XV (1911), 559-76. 32 analyses. 
The article is in Russian with a three-page résumé in German. The 
author shows that the feldspar amphibolites do not all fall into the 
chemical type of gabbro or diabase. In his 32 analyses he recognizes 
the following types: Melaphyre, Essexite, Gabbro-Norite, Vogesite 
Tephrite basalt, Shonkinite, Diabase, Gabbro-syenite Basanitic magma, 
Camptonite, two transition types, and certain special types not repre- 
sented by any known eruptive rock. 
According to texture the feldspar amphibolites are divided into four 
groups as follows: glomeroblastic, microgranitic, hornfels structure, and 
anomalous porphyritic texture. 
Emphasis is placed on the lack of identity of chemical type in the 
feldspar amphibolite group. 
ALBERT D. BROKAW 
LOEWINSON-LESSING, F. “Ueber eine bisher unbeachtet kristallo- 
chemische Beziehung,”’ Centralblatt fiir Mineralogie, Geologie, 
und Paldontologie, Jahrg. 1911, pp. 440-42. 
The writer recalls the fact that double salts and hydrates usually 
crystallize with lower symmetry than the respective simple salts and 
anhydrous bodies and proceeds to point out that such minerals as may 
be considered compounds of a silicate and a non-silicate have higher 
symmetry than the constituent silicate. As examples he cites: Nephe- 
tite is hexagonal, while noselite, sodalite, and hauynite are isometric. 
Albite is triclinic while marialite (albite+ NaCl) is tetragonal. Similarly 
helvite, danalite, melinophane, leucophane, the melanocerite group, 
and certain other complexes of this sort all develop higher symmetry 
than their silicate constituent alone. Apparently the symmetry of 
the non-silicate constituent is neglected. 
ALBERT D. BROoKAW 
SCHNEIDER, Kary. Die vulkanischen Erscheinungen der Erde. 
Berlin: Gebriider Borntraeger, r911. Pp. vilit+272, figs. and 
maps 50. M. 12, unbound. 
The author has compiled, from many scattered and sometimes not 
readily accessible sources, data on vulcanism; much of the information 
being here brought together for the first time. The presentation is 
chiefly descriptive, genetic explanations rarely being given. 
