COAST AND GEODETIC SURVEY CENTENNIAL 261 



until 1899 that an increased appropriation made it possible to under- 

 take a systematic magnetic survey oi the United States. The first 

 chart issued by the Survey (in 1855) showing the lines of equal mag- 

 netic declination was based on only about 150 values distributed very 

 irregularly near the seacoast. At the close <>f 1915 the number of sta- 

 tions was about 5000, distributed over the whole country with a fair 

 degree of uniformity, and observations had been made at about 500 

 stations in our outlying possessions. Meridian lines for the use of sur- 

 veyors had been established at many county seats, magnetic data at 

 sea had been obtained by vessels of the Survey, and magnetic obser- 

 vatories (5 since 1903) had been maintained for recording continuously 

 the countless fluctuations of the earth's magnetism. An extensive 

 compilation of the available data relating to the change of the compass 

 direction with lapse of time, combined with the systematic reoccupation 

 of old magnetic stations, has made it possible for the Survey to furnish 

 promptly information of great value in the settlement of disputed land 

 boundaries, established by compass as much as 100 or 150 years ago. 

 It may be said, without fear of contradiction, that the contributions 

 of the Coast and Geodetic Survey to the advancement of our knowledge 

 in terrestrial magnetism have not been excelled by those of any other 

 national organization. 



Dr. S. W. Stratton, Director of the United States Bureau of Stand- 

 ards: The Bureau of Standards and its relation to the United States 

 Coast and Geodetic Survey. The speaker sketched the history of the 

 various standards which have been used in this country and paid a high 

 tribute to Mr. Hassler for creating the division of weights and measures 

 of the Survey. This division became in 1904 the present Bureau of 

 Standards, a separate organization. He spoke of the close coopera- 

 tion which has always obtained between the Bureau of Standards and 

 the Coast and Geodetic Survey. 



Rear Admiral J. E. Pillsbury, United States Navy (Retired) : 

 Ocean currents and deep sea explorations of the United States Coast and 

 Geodetic Survey. After mentioning the early voyagers who came in 

 contact with and noticed the Gulf Stream, the speaker gave a brief 

 description of the first American investigation, that of Benjamin Frank- 

 lin. It was not until 1845, under the administration of A. D. Bache, 

 that the Coast Survey began a systematic study of the Gulf Stream. 

 From that year until 1853 many vessels were engaged in the work under 

 the most comprehensive orders. In 1867 Prof. Henry Mitchell of the 

 Coast- Survey began an investigation of the Gulf Stream by a new 

 method. He sounded between Key West and Havana and observed 

 currents to 600 fathoms by means of cans floating or suspended from a 

 floating can. In 1883 the first attempt was made to investigate the 

 actual flow of the Gulf Stream by a vessel at anchor, when the Schooner 

 Drift, under Lieutenant Fremont, anchored with wire rope and ob- 

 served the currents between Jupiter Inlet, Florida, and Memory Rock, 

 Bahama. The results were of so great value that the Superintendent 

 decided to continue the work. The Blake, under Lieutenant Pillsbury, 



