Results of Land Observations 57 



Special Land Investigations. 



In addition to the land work, contained in the Table of Results, there have 

 also been secured results from the above-mentioned two detailed magnetic surveys 

 made for the study of local magnetic disturbances, viz., by H. W. Fisk in the Bermu- 

 das and by L. A. Bauer near the local magnetic pole at Treadwell, Alaska; these 

 results will be given in a later publication. 



Special observations by members and associates of the Department in terrestrial 

 magnetism and in atmospheric electricity were made during the total solar eclipse 

 of August 30, 1905, at Missinaibi, Canada (L. A. Bauer and W. C. Bauer); 

 West Turnavik, Labrador (G. L. Hosmer) ; Battle Harbor, Labrador (J. E. Bur- 

 bank, E. H. Bowen, and A. H. Homrighaus); Black Point, Nova Scotia (W. G. 

 Cady); Palma, Spain (Professors Elster, Geitel, and Harms); and Tripoli, Barbary 

 (Professors Palazzo and Oddone). The following articles with reference to the 

 special instrumental outfits and apparatus, as well as the results of some of this 

 work, have already appeared in the Jourital of Terrestrial Magnetism and Atmos- 

 pheric Electricity: Atmospheric electric observations at Battle Harbor, The Labra- 

 dor, during the total solar eclipse of August 30, 1905, by J. E. Burbank, v. 12, 1907, 

 pages 97-104; A direct recording declinograph, by W. G. Cady, v. 11, 1906, pages 

 145-153 (this instrument was used by Dr. Cady at Black Point, Nova Scotia); 

 Vorschlage fiir die Ausfuhrung electrischer Beobachtungen wahrend der bevor- 

 stehenden Sonnenfinsternis, by J. Elster and H. Geitel, v. 10, 1905 (17-20); Luftel- 

 ektrische und photometrische Beobachtungen wahrend der totalen Sonnenfinsternis 

 30 August, 1905, by J. Elster, H. Geitel, and F. Harms, v. 11, 1906 (1-44); Magnetic 

 elements determined at Tripoli, Barbary, by L. Palazzo, v. 11, 1906 (93-96); 

 Measurements of the electric potential during the total solar eclipse of August 30, 

 1905, at Tripoli, Barbary, by E. Oddone, v. 11, 1906 (167-180). 



Some other land observations in terrestrial magnetism and atmospheric elec- 

 tricity have been made in connection with the following investigations already 

 published in the Journal of Terrestrial Magnetism and Atmospheric Electricity, viz.. 

 Is the Earth's action on a magnet only a couple? by L. A. Bauer, v. 13, 1908 (25-35) ; 

 On the apparent alteration of mass disclosed by weighings of magnets, by L. A. 

 Bauer, v. 14, 1909 (72-76) ; The diurnal variation of the amount of radioactive 

 emanation in the atmosphere, by P. H. Dike, v. 11, 1906 (126-129); Some atmos- 

 pheric radioactive observations made at Washington, D. C, showing the presence 

 of thorium in the air, by J. E. Burbank, v. 11, 1906 (105-107). 



