MAGNETIC OBSERVATIONS 



INTRODUCTION 



STATIONS 



The principal and most extended magnetic observations of the expedition were made at 

 Camp Abruzzi, Teplitz Bay, Rudolph Island, Franz Josef Archipelago. (This station is here- 

 after referred to simply as Teplitz Bay.) The observations here extended from September 28, 

 1903, to July i, 1904. 



A second series, covering the period June 26 to July 30, 1905, was made at Camp Ziegler, 

 Alger Island, Franz Josef Archipelago, while waiting for the arrival of the relief ship. (This 

 station is hereafter referred to simply as Alger Island.) 



Besides these primary series of observations a number of determinations (generally only of 

 declination) were made at other points. These were limited necessarily in scope by the various 

 exigencies arising, the numerous other duties of the observers, and the severe physical conditions 

 encountered. 



The observations and reductions are herein taken up in the following order of their 

 importance : 



Observations at Teplitz Bay 

 Observations at Alger Island 

 Miscellaneous observations 



INSTRUMENTS 



Through the courtesy of the Superintendent of the United States Coast and Geodetic 

 Survey, Mr. O. H. Tittmann, the expedition had the use of the following instruments belonging 

 to that Bureau : 



Magnetometer No. IIII 

 Dip circle No. 5676 



These instruments had also been loaned to the Baldwin-Ziegler Expedition of 1901 to 1902. 



The magnetometer is one of the older magnetometers of the Coast and Geodetic Survey, 

 but being large and heavy, with large magnets, was better adapted for work at a base station 

 in a cold climate than the smaller and more portable instruments. Unfortunately it was 

 discovered upon its return in 1905 that at some time, probably in the fall of 1899, six small 

 steel tacks had been used to fasten the cloth hood to the end of the maguet-house. As will be 

 seen later, these had no appreciable effect on the declination, but materially reduced the value 

 of the horizontal intensity. The necessary correction on this account has been applied to the 

 intensity results as related below. 



