Summary of the year's work, Department of Terrestrial Magnetism, Carnegie Institution of Washington

Abstract

The work of the Department during the report‐year, July 1, 1933, to June 30,1934, may be generally grouped under four divisions of endeavor. These were: (1) Reduction and study of the observational material already gathered; (2) development of methods and technique to obtain continuous records of the electrical conditions and their variations in the ionosphere ; (3) continued attack in the laboratory on basic phenomena of magnetism through experimental work in nuclear physics; (4) maintenance of field‐operations to preserve continuity of secular‐variation material and of records at observatories for seasonal, diurnal, and irregular fluctuations of the Earth's magnetic and electric field.Perhaps a most significant immediate advance is that in the ionosphere‐research which was initiated by the Department in 1925. In its latest development, it appears the most promising of recent methods of approach and one greatly enhanced by the rapid progress in nuclear physics and in wave‐propagation. It is not at the stage where continuous photographic records may be secured, manual observational methods meanwhile having shown fundamental results. This method appears also a sure means to obtain definite information not only of the conditions of the, as yet, otherwise inaccessible regions above the Earth's surface but of cosmical phenomena and of their relations to terrestrial ones. An understanding of the mechanism connecting the ionosphere and the external portion of the Earth's surface must improve knowledge of the relation of cosmical radiations in the ionosphere to their images represented by magnetic and electric phenomena at the Earth's surface and below the Earth's surface.