128 W. Huggins—Photographing the Solar Corona. 
sitive film, as in that position they would produce the least 
optical disturbance. Before the end of the telescope was fixed 
a shutter of adjustable rapidity which reduced the aperture to 
2 inches. is was connected with the telescope tube by a 
short tube of black velvet for the purpose of preventing vibra- 
tions from the moving shutter reaching the telescope. On 
account of the shortness of the exposure it was not necessary 
e 
ter some trials I satisfied myself that an appearance 
peculiarly coronal in its outline and character was to be seen 
in all the plates. I was, however, very desirous of trying 
some modifications of the method described with the hope of 
obtaining a photographic image of the corona of greater dis- 
tinctness, in consequence of being in more marked contrast 
with the atmospheric illumination, ' 
ur climate is very unpropitious for such observations, as 
very few intervals, even of short duration, occur in which the 
atmospheric glare immediately about the sun is not very great. 
nder these circumstances I think it is advisable to describe 
the results [ have obtained without further delay. 
The investigation was commenced at the end of May, 1882, 
and the photographs were obtained between June and Sep- 
tember 28th. 
