320 Scientific Intelligence. 



a notable extent in Plumas and Butte counties, Cal., and, although 

 the proportion of platinum per cubic yard of gravel is not so 

 great, the lai'ge dredging operations in Butte County make this 

 an important locality. Platinum was also found occasionally on 

 the Snake and the Columbia rivers and on various beaches of the 

 Washington coast. It was found in place in chromite near Ana- 

 cortes, Wash., as well as at the previously known locality, the 

 Rambler mine, in Albany County, Wyoming." 



It has also been found that magnetite is a prominent constit- 

 uent of the black sands of the Pacific slope, constituting a greater 

 supply of useful iron ore than that from any other available 

 source in that region. This magnetite usually contains from 5 to 

 10 per cent of titanium, but this offered no obstacle to the pro- 

 duction of high-grade cast iron in the electric furnace, and in a 

 modification of this electric furnace the cast iron could even be 

 decarburized to a very soft iron of high quality. 

 . By the use of careful concentration methods it has further 

 proved possible to separate gold and platinum from the sands 

 with comparative ease, while a partial separation of various 

 other minerals can be made at the same time, so as to render 

 available for the market at low cost : monazite, zircon, ilmenite, 

 chromite, garnet, and cassiterite. This pamphlet gives a detailed 

 statement in regard to the samples from the many different local- 

 ities represented, and also an account of the various methods by 

 which they have been examined. 



19. Miner alogia Groenlandica • af O. B. Boggild. Saertryk 

 af Meddelelser om Gronland, xxxii. Pp. xix, 625, with one 

 colored map, and 117 figures. Copenhagen, 1905 (Bianco 

 Luno). — Greenland has proved to be a most interesting source of 

 minerals from the time of the investigations of Giesecke, one 

 hundred years ago (1806-1813), to the present. Recent investi- 

 gations, particularly those with which the names of Steenstrup, 

 Johnstrup, Flink, Ussing, and of the author of the present work 

 are closely connected, have served to bring to light a wonderful 

 series of new species and interesting occurrences, especialh^ on the 

 southwest coast at Kangerdluarsuk and Narsarsuk, near Julian- 

 ehaab. The cryolite locality at Ivigtut and the region about 

 Disco, with its remarkable supply of telluric iron, have also 

 furnished much that is new and important. Dr. Boggild has 

 now brought together all the information that has been developed 

 in regard to these and other localities, and has presented it in a 

 concise and systematic form in the present handbook. It will serve, 

 therefore, as a very convenient source of information in regard to 

 some of the very interesting mineral occurrences that are known. 

 The species are arranged after Groth's tables, and the occurrences 

 of each of the localities are given with admirable fullness. 



The closing chapters of the work are devoted to a geogi-aphical 

 list of all the Greenland localities, followed by an alphabetical 

 index. There is also a map, which is important for those who 

 are not minutely acquainted with the geography of the country. 

 The preface, by "N". V. Ussing, is in English, as is also the short 

 summary of contents with which the work closes. 



