RECENT PROGRESS IN GEODESY. 
141 
so far fully justifies the changes made. The lines of level" 
ing are being rapidly extended, a total of 1,750 miles having 
been run during the last two years. 
The most marked progress, however, in the matter of 
leveling has been the adjustment of the level met covering 
the eastern half of the United States. More than 13,000 
miles of precise leveling had been run by various organiza¬ 
tions in the United States. But until within a year the re¬ 
sults had not been correlated. To obtain the results it was 
necessary to search through scores of volumes, and even 
when this had been done it was found that the results had 
been published as if each line or group of lines was entirely 
independent of the others, whereas in fact the connections 
existed for treating the whole as a single net upon one 
basis. The adjustment of this net has now been made. 
The elevations and descriptions of the four thousand perma¬ 
nent bench-marks connected with the net and the principal 
items of information in regard to each of the lines have 
been published in a single volume.* 
During the year the report upon the transcontinental 
triangulation, which marks an epoch in the history of ge¬ 
odesy in the United States, has been published.! The com¬ 
putation of the eastern oblique arc, extending from Maine 
to Louisiana, has been also completed,! and the report will 
soon be ready for the printer. The relations between the 
measures of the earth made in the United States and the 
previously accepted values for the earth’s size are shown in 
the table given below. 
* See Appendix 8 of the Coast and Geodetic Survey Report for 1898- 
1899, pp. 347-886. 
f The Transcontinental Triangulation, Special Publication No. 4, of the 
Coast and Geodetic Survey, Washington, 1900, 4to, 871 pages. 
X See “ Recent Contributions to our Knowledge of the Earth’s Shape 
and Size by the United States Coast and Geodetic Survey.” C. A. 
Schott, The National Geographic Magazine, January, 1901, pp. 36-41. 
