92 S&P. Langley—Minute structure of the Solar Photosphere. 
theory we adopt, we may admit the contingency of a more 
general distribution than is at first apparent, while recognizing 
that we can number those distinctly visible, and can compute 
the area they expose, without fear that our estimate will induce 
material error from the neglect of the existence of other of 
these bodies relatively non-luminous, which with more power- 
ful instruments might conceivably be discerned. 
n fact, the prevalent impression that the brilliant bodies to 
which the photospheric light is chiefly due are so closely set that 
only minute dots or shades of thread-like narrowness appear be- 
tween, is, I venture to state, incorrect. I hardly think it can be 
shared by one who, after his attention is directed to this point, 
has the opportunity of studying them under circumstances 0 
reduced irradiation, when these bodies are seen to occupy the 
smaller portion of the area they at first appear to fill. Inde- 
gra ay be as much as “4, and the number to the square 
two hundred, I still find that the properly luminous area is Jess 
than one-fifth of the solar surface. 
script of sketches taken at the telescope, and which were, when- 
ever possible, completed and compared before leaving it. 
