302 CARNEGIE INSTITUTION OF WASHINGTON. 



4. Two accessory huts used formerly for standardizing and testing mag- 

 netic instruments, but now available for researches in cosmophysical 

 subjects. With the initial equipment, the total cost of 1,2, 3, and 

 4 approximates $128,000. The magnetic observatory (3) was erected 

 in 1914 by the Department itself, under the direct supervision 

 of Mr. J. A. Fleming. 



It is furthermore hoped that in 1915 a tower about 80 feet high 

 may be erected, on which a hut (12 by 12 feet) may be built to house 

 atmospheric-electric instruments. 



Thus the Department of Terrestrial Magnetism is rapidly acquiring 

 exceptional facilities for its varied work, both in the field and allied 

 subjects. With the expected near completion of its first great obser- 

 vational task — the general magnetic survey of the Earth — the time is 

 ripe to take the initial steps for other world-wdde projects outlined in 

 the program of work of this Department (see Year Book No. 2, for 

 1903, p. 204), for example. International observations of the variations 

 of the Earth's rnagnetism. This requires the establishment and main- 

 tenance for a term of years of observatories at certain fixed points, 

 the location of which is to be determined wdth reference to the existing 

 institutions, so as not to duplicate but rather to supplement in the 

 required effective manner. 



With the end in view just stated, preliminary exaininations of sites 

 have already been made in the past by our various land expeditions. 

 Battle Harbor, Labrador, or vicinity would be a very suitable location 

 for an observatory such, as contemplated. Polar lights occur here fre- 

 quently^ and the opportunities for combined research in terrestrial 

 magnetism and terrestrial electricity (polar lights, telluric electric cur- 

 rents, and atmospheric electricity) w^ould be excellent. The Bermudas 

 and Bahamas would also afford good sites, but cosmophysical observa- 

 tories require supplementing, especially in the Southern Hemisphere. 

 Should interruptions occur in the prosecution of the magnetic-survey 

 work in 1915, because of war conditions, it would be desirable to 

 inaugurate the field-observatory work. It may be mentioned that 

 the establishment of such observatories is also urgent for supplying the 

 data needed in the reduction of the magnetic-survey work to a common 

 «poch and to keep our proposed world magnetic charts corrected to date. 



The existing observatories are insufficient in number and are inade- 

 quately distributed. For example, about half of the total number of 

 magnetic observatories are located in Europe and only about 15 per 

 cent of them are in the Southern Hemisphere. In brief, the present 

 distribution of magnetic observatories is inter-European rather than 

 international, as is required for the successful solution of the great 

 problems concerning the causes of such world-wide phenomena as, for 

 example, the diurnal variation of the magnetic needle; magnetic storms 

 which in a moment's time may derange the entire magnetization of 



