Total Eclipse of August 7, 1869. 191 



knowledge of them. By means of this we are able to dis- 

 tinguish a solid body from a gaseous, a self-luminous from 

 a reflective body, and even more, to determine with 

 certainty the very elements comprising the incandescent 

 body. This mode of investigation, used first in the total 

 eclipse of 1868, and still more in that of the recent eclipse, 

 has revealed to us that the red protuberances are mainly 

 a mass of incandescent hydrogen gas. The thought is 

 overpowering. Here are vast accumulations of blazing 

 matter reaching to a height of many thousand miles. 

 "What convulsions in the matter of the surface of our sun 

 does this view of it reveal ! 



"That the spots which are seen on the surface of the sun 

 will finally be proved to be identical with the protube- 

 rances, I venture to predict." 



The most remarkable of the red flames, is that repre- 

 sented at the top of the drawing. It was seen nearly a 

 minute previous to totality, and remained visible almost 

 six minutes after totality had ended. We had it under 

 observation during nearly the whole duration of the total 

 eclipse. Its height was measured with the parallel wire 

 micrometer, and found to be 1' 05", equivalent to 30,000 

 miles. It may be necessary to state, that the micrometer 

 screw head was not read until after the end of totality. 

 The fixed wire then stood between two movable ones, di- 

 viding the interval in spaces of 1' 05", and 2' 45". We 

 assumed the smaller interval as the height of the protube- 

 rance ; but on discussing the subject with the other ob- 

 servers, it was considered altogether too small. We 

 thought it possible, there might have been a mistake in 

 the interval used, and accordingly adopted the largest 

 measure. But observations made at other points seem to 

 show conclusively, that the smaller measure is the correct 

 one. Its position was 20° to the apparent north of the 

 equator, and its base was estimated at three times its 



