ABSTRACTS 



Authors of scientific papers are requested to see that abstracts, preferably 

 prepared and signed by themselves, are forwarded promptly to the editors. 

 Each of the scientific bureaus in Washington has a representative authorized to 

 forward such material to this journal and abstracts of official publications should 

 be transmitted through the representative of the bureau in which they originate. 

 The abstracts should conform in length and general style to those appearing in 

 this issue. 



GEODESY. — Report of the Superintendent of the Coast and Geodetic 

 Survey, showing the progress of the work from July 1, 1909, to June 

 30, 1910. 454 pp., 4 maps and 5 progress sketches in pocket. 1911. 



The administrative portion of this report recounts briefly the progress 

 of work in field and office for the fiscal year ending June 30, 1910, cover- 

 ing the coasts under the jurisdiction of the United States. It also 

 reports the progress made in surveying and marking the United States 

 and Canada Boundary and the Alaska Boundary, under the direction 

 of the Superintendent as United States Commissioner. Observations 

 to determine the relative force of gravity at 27 stations in 14 States 

 form an important contribution to the gravitation survey of the country. 

 The magnetic survey was extended by making observations at 238 

 stations on land and at numerous stations at sea. Continuous obser- 

 vations with self-registering instruments were obtained at five magnetic 

 observatories widely distributed over the country. Records of tidal 

 changes were obtained at 15 widely separated stations. 



A notable event of the year was the completion, in the instrument 

 shop of the Survey, of a tide predicting machine, elsewhere described 

 in this journal. 



The report refers to the important contribution to the science of 

 Geodesy made by the Survey in publications entitled "The Figure of 

 the Earth and Isostasy from Measurements made in the United States" 

 and " Supplementary Investigation in 1909 of the Figure of the Earth 

 and Isostasy," which furnish a determination of the figure and size of 

 the earth of a high grade of accuracy and which, by somewhat novel 

 methods have established the fact that in and around the United States 

 a condition of isostasy exists. This work was laid before the last General 

 Conference of the International Geodetic Association and received formal 



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