6 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



in dividing the protuberances into three classes, according to 

 their direction in relation to the poles, the following figures 

 may be given : 



Indifferent 398 



Directed toward the poles 342 



Directed toward the equator 67 



Total 807 



6B,May 20,1872,1315. 



YELLOW BRIGHT LINE OF THE SOLAR PROTUBERANCE 



SPECTRUM. 



Professor D' Arrest, of Copenhagen, calls attention to the 

 circumstance that, although the origin of the yellow bright 

 line D 3 of the solar protuberance spectrum is entirely un- 

 known, still that line is never seen except in company with 

 the lines C and F, or, in other words, Ha and H/3. From a 

 consideration of this fact, and bearing in mind that D 3 is sit- 

 uated between Ha and H/3, while Hy is situated between H/3 

 and H<), he has been led to the discovery that, in respect to 

 the number of vibrations made by the light wave in a given 

 time, D 3 is related to Ha and H/3 in the same manner that the 

 logarithm of Hy is related to the logarithms of H/3 and He). 



In the case of nebulae giving a spectrum consisting of three 

 bright lines, the same relation holds between the middle line 

 and the two outside ones ; but in the case of comets, many 

 of which also give a spectrum consisting of three bright lines, 

 the relation does not hold. Astronomische Nachrichten. 



REPORT OF THE U. S. NAVAL OBSERVATORY ON THE ECLIPSE 



OF DECEMBER, 1870. 



The long-expected report of the United States Naval Ob- 

 servatory upon the total solar eclipse of December 22, 1870, 

 has just been published, as prepared under the direction of 

 Admiral Sands, the superintendent. As is known to most 

 of our readers, this eclipse was not visible in the United 

 States; but several professors from the Observatory were 

 sent abroad to assist in the investigation of the phenomena in 

 Europe. Of these, Professor Simon Newcomb was stationed 

 at Gibraltar, and Professors Asaph Hall, William Harkness, 

 and J. R. Eastman at Syracuse, in Sicily. The foreign savants 

 associated with these gentlemen bore honorable testimony to 



