DEPARTMENT OF TERRESTRIAL MAGNETISM. 331 



Comparisons of magnetic observatory standards. — An extensive series 

 of such comparisons with the Department's standards was obtained 

 at various places and will be found mentioned in the respective field 

 reports. Furthermore, Dr. Otto Klotz, director of the Dominion 

 Observatory of Canada, kindly communicated the results of com- 

 parisons made at different times during 1915 to 1920 between the 

 Dominion Observatory magnetometer No. 20 of the C. I. W. universal 

 type^ and the standards of the Agincourt Magnetic Observatory. 

 At Dr. Klotz's request, comparisons were made during May and June 

 1921 at Washington between Dominion Observatory magnetometer 

 No. 20 and the Department standard magnometer No. 3. Accordingly, 

 indirect comparisons between the adopted Agincourt standards and 

 those of the Department were also obtained. 



Observatory Work of MacMillan Baffin Land Expedition. — The plans 

 were completed for proposed temporary observatory work at the 

 winter-quarters of the MacMillan Baffin Land Expedition (see pp. 

 327 and 334). A small non-magnetic building for the installation 

 of magnetograph and of potential-gradient apparatus was designed 

 and the necessary materials and instrumental accessories were pur- 

 chased and constructed. The magnetograph to be used is of the 

 Eschenhagen type and includes variometers for decUnation, hori- 

 zontal intensity, and vertical intensity; the latter variometer was 

 courteously loaned by the U. S. Coast and Geodetic Survey. The 

 potential-gradient apparatus was designed and constructed in the 

 Department. 



'See "Researches of the Department of Terrestrial Magnetism," Vol. II, 7-9, 1915. 



