682 Scientific Intelligence. 



Harper (pp. 163-343). The Director of the Florida Survey has 

 been unusually successful in maintaining the two-fold function of 

 the organization: economic and educational. The physiographic 

 and economic publications in particular are to be commended. 



H. E. G. 



3. Biennial Report of Topographic and Geologic Survey of 

 Pennsylvania for the two years ending June 1, 1914. Pp. 232, 

 pis. I-V. — Of 240 quadrangles into which the State of Pennsyl- 

 vania has been divided, 144 have been covered by topographic 

 maps on a scale of 1 : 62500 with 20-foot contours. Geologic 

 surveys cover 31 quadrangles. A series of reports dealing with 

 the mineral wealth of the state from year to year engages the 

 chief attention of the staff, an emphasis on economic geology 

 justified by the fact that 24 per cent of the total mineral produc- 

 tion of the United States is credited to Pennsylvania. The 

 present report includes papers on the Copper Development of the 

 South Mountain Region by G. M. Bevier, and Mineral Produc- 

 tion of Pennsylvania for 1912. Papers dealing with the slate 

 industry and the clay industry are in process of preparation. 



H. E. G. 



4. Geological Survey of Illinois: Frank W. DeWolf, 

 Director. Bulletin No. 24, Some Deep Borings in Illinois, by 

 J. A. Udden. Pp. 141, pis. I-IV (last three in pocket). — The 

 stratigraphic value of carefully collected samples obtained by 

 drilling is evident. Particularly in regions of slightly dissected, 

 flat-lying rocks a few well records correctly interpreted may 

 yield more valuable geologic data than could be obtained by the 

 study of many square miles of surface exposures. The relatively 

 little attention given to this source of information doubtless 

 results from unsatisfactory experience with logs as frequently 

 recorded. Professor Udden shows, however, that modern methods 

 of drilling are suitable for geologic purposes and he discusses 

 methods of examination best designed to secure correct interpre- 

 tation. For the formations underlying the surface of Illinois the 

 thickness and number of strata have been determined on the basis 

 of well sections, with the result that the lithologic variations and 

 sequence of beds may be discussed on a quantitative basis. 



h. e. g. 



5. Publikationer fra det Danshe Meteor ologiske Institute 

 ved C. Ryder, Direktor, Aarboger. Isforholdene i de Arktiske 

 Have (The State of the Ice in the Arctic Seas, 1914). 1915. Pp. 

 xxiv, 5 maps. — Like the publications dealing with the annual 

 fluctuations of the world's glaciers, the reports of the annual (in 

 many cases monthly) distribution of ice in the arctic seas fur- 

 nishes detailed climatologic data of high significance. The value 

 of the data is proportional to the number of years for which 

 observations are recorded and it is to be hoped therefore that the 

 work undertaken may be continued and its scope increased. It 

 is gratifying to professional workers in geography that captains 

 of sealers, fishing schooners, and freighters, as well as scientific 



