4 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



Xeres, under charge of Professors Winlock and C. A.Young. 

 They had four or more spectroscopes, of which two were 

 used by English volunteers. Their observations confirmed 

 the existence of bright lines in the spectrum of the corona, 

 which had been observed by Harkness and others in 1869, 

 but which the English astronomers were slow to believe in. 

 The most remarkable of these lines is a green one, supposed 

 to be identical with one of the lines of iron, and with the line 

 found by Angstrom in the aurora and in the zodiacal light. 

 This line was traced by Professor Winlock to a distance of 

 near 20' from the sun's limb. Professor Young traced it 16' 

 on the west, 12' on the north, 14' on the east, and 10' on the 

 south. 



The other two spectroscopes were arranged so as to collect 

 the light from the entire corona and protuberances at once. 

 With one of these Mr. Abbay saw only two lines the one 

 just referred to, and the other the F line. With the other 

 Mr. Pye saw also the lines C and D3. All except Mr. Abbay 

 saw a faint continuous spectrum without dark lines. 



But the most interesting observation was the following by 

 Professor Young : " Just previous to totality, I had carefully 

 adjusted the slit tangential to the sun's limb at the point 

 w r here the second contact w T ould take place, and was watch- 

 ing the gradual brightening of 1474 and the magnesium lines. 

 As the crescent grew narrower I noticed a fading out, so to 

 speak, of all the dark lines in the field of view, but was not 

 at all prepared for the beautiful phenomenon which present- 

 ed itself when the moon finally covered the whole photo- 

 sphere. Then the whole field was at once filled with bril- 

 liant lines, which suddenly flashed into brightness and then 

 gradually faded away, until in less than two seconds, nothing 

 remained but the lines I had been watching." There can be 

 little doubt that these bright lines emanate from the same 

 atmosphere, the absorption of which causes the dark lines of 

 the spectrum, the same rays which, by contrast, look dark 

 alongside of sunlight, being bright when the sunlight is cut 

 off by the moon. The existence of this atmosphere was long 

 ago inferred from the dark lines of the solar spectrum, and 

 Secchi had inferred that it formed a very thin layer over the 

 surface of the photosphere, from noticing that the dark lines 

 faded out at the extreme edge of the sun; but Young was, 



