■±10 Scientific Intelligence. 



of rock types. It would be impossible in a brief notice to give 

 any account of the large amount of information contained in this 

 volume, mostly of a detailed local character, but those interested 

 in petrography on the one hand, and those who are concerned 

 with the ecomonic features, such as the gold deposits, on the 

 other, will find in it much that is of general importance, l. v. p. 



4. Essai sur la Constitution geologique de la Cuyane hollan- 

 claise (district occidental); par H. Van Cappelle. Etude petro- 

 graphiqne; par E. H. M. Beekman. 8°, pp. 177 and map. Paris, 

 1907. — This work contains an account of geological observations 

 made during voyages of exploration along the south bank of the 

 Corantyn (Corentyne) River and along the Nickerie River and 

 one of its branches. The observations are necessarily confined to 

 a narrow strip along the route traversed. Metamorphic rocks 

 consisting of various gueisses, quartzites and schists were observed, 

 frequently cut by igneous masses, granites, diorites and gabbros 

 being most prominent, although other types of rocks also occur. 

 The author discusses the alteration of these rocks and also the 

 character of the soil formed, especially that of laterite. He de- 

 scribes the distribution of gold and its relation to the rock forma- 

 tions. The petrographic study consists of a description of the 

 mineral composition of the large number of rock specimens 

 collected, as seen in thin section under the microscope. 



While the work was in the nature of a rapid reconnaissance, it 

 adds considerably to our knowledge of a little known region. 



L. V. P. 



5. The Eruption of Vesuvius in April, 1906; by H. J. 

 Johnston-Lavis, Sci. Trans. Roy. Dublin Soc, Vol IX, Pt. 8, 

 Jan. 1909. 4°, pp. 139-200, pis. iii-xxiii. — The author, who has 

 long been known for his studies of Italian volcanic phenomena and 

 especially of Vesuvius, gives in this paper a general account of 

 this eruption with special details upon certain phases. Outside 

 of these latter, which deal chiefly with a discussion of the petrog- 

 raphy of the products of the eruption and of certain views con- 

 cerning volcanic action which the author has developed as a 

 result of his studies, the memoir furnishes an excellent general 

 description of the eruption and its attendant phenomena; this is 

 made graphically interesting by a series of plates reproducing 

 excellent photographs. In addition two maps add greatly to its 

 value. L. v. p. 



6. Text- Book of Petrology ; by F. H. Hatch. 12°; pp. 404; 

 5th ed., 1909. London (Sonnenschein & Co.). — This little volume, 

 which contains a short account of the general principles of petro- 

 logy, has been rewritten and given a general redressing by the 

 author. Since such subjects as the rock minerals and their 

 characters under the microscope, the physical characters of rocks, 

 their modes of occurrence and classification, rock textures and a 

 variety of others are dealt with in the first 150 pages, these sub- 

 jects are necessarily handled in a very brief and elementary wa}^ 

 The following 125 ^pages are devoted to a general description of 

 igneous rocks, these being divided into the plutonic, hypabyssal 



