Geology and Mineralogy. 463 



netitly developed in Ohio will give these Bulletins much value. 

 The first report to be completed is that on the Manufacture of 

 Roofing Tiles, an industry which thus far has been somewhat 

 slow to develop in this country, although in the history of the 

 subject we have to go back to 1814 for the time when tiles were 

 first made use of in the state ; this was at Germantown, a village 

 some 30 miles northeast of Cincinnati. Roofing tiles have, aside 

 from the non-permanent wooden roof, various rivals in the slates, 

 corrugated iron, asbestos, and other artificial fabrics, and cement; 

 but the future is likely to see a larger development in the direc- 

 tion which has had so much use in foreign countries. The author 

 of the present work has been engaged in the practical industry 

 for a number of years, and hence is able to discuss the various 

 aspects of the subject with all needed fulness and accuracy. 



9. Elements of Geology ; by Eliot Blackweldek and Harlan 

 H. Baerows. Pp. 467, 16 plates, 485 figures. New York, 1911 

 (American Book Company). — No attempt is made in this book to 

 present new material or to discuss controversial matter. It is a 

 text-book pure and simple and the selection of topics as well as 

 the manner of presentation has been determined by that fact. 

 The book shows clearly that its authors are experienced teachers 

 and understand what is and what is not within the intellectual 

 range of students who have not previously studied the subject. 

 The text is rather too brief for use in colleges, but should find 

 a place in institutions where short courses are given to students 

 of elementary science. H. E. G. 



10. A Remarkable Crystal of Beryl; by George F. Ktjnz 

 (from a paper read before the New York Academy of Sciences, 

 April 3d, 1911).— On the 28th of March, 1910, in a pegmatite 

 vein at Marambaya, a village in the vicinity of Arassuahy, on the 

 Jequitinhonha River, in the State of Minas Geraes, Brazil, there 

 was found a crystal of beryl, which was the largest crystal of 

 precious beryl (aquamarine) ever found. In form it was a simple 

 hexagonal prism with slight irregularities due to compression, and 

 terminated with a simple basal plane at both ends. , The crystal 

 weighed 110*5 kilograms, was 48-5 centimeters high, and from 

 40 to 42 centimeters in its different widths. It was so trans- 

 parent that, looking down into the crystal through its basal 

 termination it could be seen through from end to end. In color 

 it was greenish-blue, absolutely free from included impurities but 

 traversed by a number of fractures. 



This crystal was found by a Turk, who mined it in what is 

 known as a primitive mine, at a depth of from five to six meters, 

 and only with the greatest difficulty was it transported by canoe 

 to the coast, by way of the Jequitinhonha River and then shipped 

 to Bahia, where it is said that he realized $25,000 for it. It is 

 estimated that this crystal would furnish at least 200,000 carats 

 of aquamarines of various sizes. 



11. The Mineralogy of Arizona ; by F. N. Guild. Pp. 99. 

 Easton, Pa., 1910 (The Chemical Publishing Co.) — This is a useful 



