302 Dr. Herschel’s Observations to investigate 
those biases which have been shewn to affect the direction of a 
number of shallows at the same time, must have arisen from a 
motion of the atmospheric gases under the clouds ; and, that 
there is a considerable vacant space between these clouds and 
the solid body of the sun, is also to be inferred, from the free 
motion of clouds considerably lower than usual, which were 
seen to pass over an opening, and which cannot be supposed to 
have rolled over the ground in contact with it. Without, how- 
ever, entering into any particular examination of the amount of 
the distance from the sun to the first cloudy regions, which, were 
I to guess by some pretty obvious circumstances, would not be 
less than some hundreds of miles, we may take it for granted, 
that the altitude of the clouds will every where be determined 
by their own density, and by that of the atmosphere in which 
they are suspended. 
The Sun’ s planetary Atmosphere is transparent. 
It will be easily shewn, that the gases of the solar atmosphere 
are transparent ; for we have already given observations that 
prove our being able to see the reflected light of the corru- 
gations from their indentations ; and of the self-luminous regions 
in general, from the shallows which they surround and illumi- 
nate. To this may be added, that we also see clearly down 
through the space which leads through the openings, as fully 
appears from our being able to see the thicknesses of the bor- 
ders which inclose them. We have likewise given an instance 
of seeing the limb of the sun broken by a vacancy proceeding 
from a large shallow ; though undoubtedly that shallow must 
have been covered, with the solar atmospheric gases. 
