58Q REPORT— 1903. 



been inaugurated. This plan, in brief, was to first make a general survey with 

 stations about 25-30 miles distant from one another, and to occupy about 400-500 

 stations a year. After the general survey had been completed, additional stations 

 were to be placed in the locally or regionally disturbed areas developed by the 

 general survey. On the average there was to be a ' repeat ' station for an area of 

 ten stations. A period of ten to fifteen years was expected to be consumed in 

 the general survey. The area to be surveyed, not counting the adjacent seas, 

 embraces one-fifteenth of the entire land area of the globe, or an area equal to 

 that of Europe. 



Up to June of the present year nearly one-third of the total number of stations 

 contemplated for the general survey, viz. about 1,2.50 stations, have been completed. 

 Five magnetic observatories have been established — Cheltenham (Maryland), Bald- 

 win (Kansas), Sitiia (Alaska), Honolulu (Hawaiian Islands), and Vieques Island 

 (Porto Rico). A sixth is contemplated for the north-western part of the United 

 States. In addition, a variety of miscellaneous preliminary investigations relating 

 to methods of work and reduction and the standardisation of instruments have 

 been made, and several publications have been issued. During this year magnetic 

 work at sea has been commenced on board the vessels of the Coast Survey, 

 The reduction of the field work has been kept apace with the observational worlf, 

 so that the results obtained during any one year are published within a few 

 months after the close of the year. 



With the successful completion of the arduous initial work attendant upon 

 the inauguration of so vast a magnetic survey, and the systematisation of the 

 various operations in the field and in the office, and having trained the necessary 

 observers, we may look forward to the continuation of the work with even greater 

 rapidity than that of the past four years, and it is confidently believed that the 

 general magnetic survey will be completed at about the close of the present 

 decade. 



I shall again express the hope that Canada may soon be able to follow the 

 example of the United States. 



The chart exhibited shows the number and positions of the magnetic stations 

 in the United States up to June 30, 1903. 



10. The Eurth's Total Magnetic Energy.^ By L. A. Bauer. 



WEDNESDAY, SEPTEMBER 16. 



The following Papers and Report were read : — 



1. A Probable Relationship between the Solar Prominences and Corona. 

 By William J. S. Lockyer, M.A., Ph.D., F.R.A.S. 



This Paper has already appeared in the ' Monthly Notices of the Royal Astro- 

 nomical Society ' (vol. Ixiii. No. 8, 1903). The object of the investigation is to 

 suggest that the different forms of the corona are intimately connected with the 

 latitudes of the prominences. A summary of the conclusions arrived at is as 

 follows : — 



1. The ' forms ' of coronas may be grouped generally into three classes, here 

 named ' polar,' ' intermediate,' and ' equatorial,' according as the streamers appear 

 near the solar poles, in mid-latitudes, or about each side of the equator. 



2. The sequence of these forms, if sufficient numbers of eclipses occurred, 

 should be equatorial, intermediate polar, intermediate equatorial, &c. 



3. The various forms of the corona are closely connected with the positions 

 (as regards latitude) of the centres of action of the solar prominences. 



' Published in full in Terrestrial Magnetism, September 1903. 



