4 86 SCIENCE PROGRESS. 



BIBLIOGRAPHY. 



(i) Roth, Justus. Die Gesteinsanalysen in tabellarischer Ueber- 

 sicJit und mit kritischen Erlaiiterungen. 4to. Berlin, 1861. 

 [The rocks are grouped according to the dominant felspar, 

 orthoclase, oligoclase, labradorite, or anorthite, with subdivi- 

 sions characterised by quartz, augite, hornblende, etc. ; but 

 there is frequent reference to Bunsen's law as expressing the 

 mutual relations of the rocks in chemical composition.] 



(2) Lawrence, Philip Henry. Lithology: or Classification of 



Rocks, zvith their English, French, and German names . . . 

 according to the system of BernJiard von Cotta. 4to. London, 

 1865. [A synoptical table only: see next entry.] 



(3) COTTA, BERNHARD VON. Rocks Classified and Described : a 



Treatise on Lithology ; an English edition [of Die Gesteins- 

 lehre\ by Philip Henry Lawrence. 8vo. London, 1866. 

 [The only systematic grouping of the normal igneous rocks 

 is into " basic " and " acidic," each divided again into " vol- 

 canic " and " plutonic ".] 



(4) Zirkel, Ferdinand. Lehrbuch der Petrographie. Two vols., 



8vo. Bonn, 1866. [The composite crystalline-granular rocks 

 aregrouped under orthoclase-rocks,oligoclase-rocks,nepheline- 

 and leucite-rocks, labradorite-rocks, and anorthite-rocks, with 

 subdivisions. There is further a separation between " older " 

 rocks, divided according to structure into phanerocrystalline, 

 porphyritic, and cryptocrystalline ; and "younger" rocks, 

 divided into crystalline and glassy. This classification, with 

 various modifications, has been widely used.] 



(5) DAUBREE, A. Classification adoptee pour la collection des roches 



du Musee d' Histoire Naturelle de Paris. 8vo. Paris, 1867. 

 [A rough mineralogical classification, the igneous rocks figur- 

 ing under the six groups, " felspathiques," " pyroxeniques et 

 hyperstheniques," " amphiboliques," " epidotiques et grena- 

 tiques," " micacees," and " silicatees magnesiennes ".] 



(6) Richthofen, F. von. Principles of the Natural System of 



Volcanic Rocks. Mem. Calif Acad. Sci, vol. i., pp. 39-133, 

 1868. 

 RICHTHOFEN, F. VON. Die natiirliche Gliederung und der 

 innere Zusammenhang der vulkanischen Gesteine. Zeits* 

 Deuts. Geol. Ges., vol. xx., pp. 661-726, 1868. 



(7) MEUNIER, STANISLAS. Nouvel Arrangement Methodique des 



Roches. Vers/. Meded. Kon. Akad. {Amsterdam) afd. natuurk. 

 (2), vol. iv., pp. 269-283, 1870. [An example of a remark- 

 ably artificial system, the main divisions being founded on 



