136 Chronicles of Science. [Jan., 



necessarily increases in its proportions, and a glance at the index is 

 sufficient to show that among the many new species — or reputed 

 species — constantly being brought to hglit, there are but few that 

 escape the notice of the great crystallographer of Leipzig. 



A laborious compilation, by Dr. Websky, of Breslau, claims a 

 passing notice as the first of a series of mineralogical monographs.* 

 This is httle else than a bald hst of all the known mineral species, 

 classified in groups according to their specific gravities, commencing 

 with Pyropissite, which has a density as low as 0'493, and ending 

 with Iridosmium, with a density as high as 21 "2. The specific 

 gra\T.ty is usually accompanied by the hardness, and sometimes by 

 the chemical composition of the mineral. It is supposed by the 

 author that the few characters here given will be sufficient to guide 

 the student in the determination of species. 



Neio Worhs on Petrology. — Probably it would be difficult to 

 point to any branch of natural science which at the present time 

 occupies a more unsatisfactory position in this country than that 

 science which, according as it is pursued in the field or in the cabinet, 

 has been variously designated Petrolor/ij or Lithologu ; in other 

 words, the study of rocliS as distinguished from that of minerals. 

 AVhilst we have pursued stratigraphical geology in a spirit worthy of 

 the countrymen of WiUiam Smith, and have prosecuted the study of 

 fossils with such vigour, and consequently with such success, that 

 British palaeontologists and their writings enjoy a world-wide repu- 

 tation, it is strange that the complementary science of petrology 

 should have fallen into unmerited neglect, and that in this depart- 

 ment our best geologists should be found sadly wanting when 

 weighed against their brethren of the hammer in other lands. 

 Place, for example, the Journal of our own Geological Society by 

 the side of the Zeitschrift of the corresponding Grerman Society, 

 and our shortcomings on this point are all too plainly seen. The 

 geologist, therc^fore, who would describe with accuracy the rocks 

 that are forced upon his observation in the course of his daily work, 

 must needs betake him to the fields of continental literature, where 

 the fertility that has been evoked by many a painstaking labourer 

 strikingly contrasts with the sterihty at homo. Especially in the 

 rich literature of Germany does he find no lack of treatises which 

 exhilnt that happy combination of chemical, mineralogical, and 

 geological knowledge, without which the study of petrology would 

 be next to impossible. Not to mention a host of minor writings, it 

 is sufficient to point, in support of our assertion, to the admirable 

 works of Senft and Zirkcl. As a fit introduction to these compre- 



* ' Die Mineral-Species, naeh den fiir das spccifisclio (^owicht dersolben 

 angenommeu und gefunden Wcrtben. Ein Hiilfsbueh zur bostinimtudeu Miue- 

 ralogie.' Von Dr. Martin Websky. 4to. Breslau, 1868, pp. 170. 



