232 REPORTS ON INVESTIGATIONS AND PROJECTS. 



WORK IN WASHINGTON. 



In addition to the final reduction of the field observations, the manuscript 

 was completed of the first volume of researches of the Department contain- 

 ing the results of all land observations made by observers of the Depart- 

 ment between 1905 and 1910 at about 1,500 stations. This publication is 

 now in press. The Director has continued his researches on the physical 

 theory of the Earth's magnetic and electric phenomena and has published 

 three papers on the results obtained. Dr. N. E. Dorsey, Research Asso- 

 ciate, completed an investigation involving the complete theory of the earth- 

 inductor and the applicability of this instrument to the measurement of the 

 magnetic dip on board the Carnegie. As the result of these studies, an 

 instrument was constructed in the workshop of the Department after the 

 design of Messrs. Dorsey and Fleming, and was supplied to the Carnegie 

 at Tahiti in September. Under the heading "Shopwork" further informa- 

 tion will be found as to the instruments constructed by the Department. 



SPECIAL OBSERVATIONS DURING THE TOTAL SOLAR ECLIPSE, OCTOBER 10, 1912. 



Besides special magnetic observations by observers of the Department on 

 the day of the eclipse, cooperation was secured from various institutions in 

 North and South America. Furthermore, Prof. Walter Knoche, Director of 

 the Instituto Central Meteorologico y Geofisico de Chile, proceeded from 

 Santiago, Chile, under the joint auspices of his Institute and the Carnegie 

 Institution of Washington, to a station in the belt of totality, in the south- 

 eastern part of Brazil, and made atmospheric, electric, and allied observations. 



The Director takes this opportunity to acknowledge his indebtedness to 

 the various members of his staff for the work accomplished during the year. 



DETAILS OF MAGNETIC WORK DURING THE YEAR. 



LAND WORK. 



Africa. — Upon completing his work in Italy and Malta, Observer W. H. 

 Sligh made magnetic observations in northern and northwestern Africa, 

 occupying 32 stations in Tunis, Algeria, and Morocco, and 2 stations in the 

 Canary Islands. A number of these occupations gave valuable secular 

 variation data. From the Canary Islands he carried out successfully an 

 unusually difficult and hazardous trip by small boat along the coast of Rio 

 de Oro and Mauretania to St. Louis, Senegal, where he arrived the latter 

 part of July, having determined the three magnetic elements at 10 stations. 

 After observing at 3 stations in French West Africa he went to Algiers, 

 where, during September, he assisted Observer D. W. Berky in his prepara- 

 tions for an expedition across the desert of Sahara to Timbuktu. At the 

 close of the fiscal year Mr. Sligh was still engaged in Algiers. 



