146 Proceedings of the Boyal Society of Edinburgh. [Sess. 
tamed close to the surface by the turbulent motion of the wind in that 
region. In the case of a north wind, possibly a curve of type A E D is 
changed to one of type BED when the air reaches warmer seas than 
those over which it has passed. This process may even cause stratus 
clouds at rather higher levels, such as those of June 16, already referred 
to ; but until more knowledge is available of the temperatures over the 
Arctic Sea, such an explanation must be considered as improbable for 
stratus layers at a greater height than 2000 feet above the surface.* 
Summary. 
The following is a summary of the more important conclusions which 
have been put forward in this paper : — 
1. The Nature and Distribution of Stratus in Anticyclones . 
(1) Stratus clouds have an adiabatic temperature gradient below them, 
and a reversed gradient above them ; within the cloud the gradient 
is usually adiabatic. The same relations hold for well-defined layers 
of haze. 
* See Note at end. The turbulent motion of the lower strata may reduce the tempera- 
ture of layers even above 2000 feet, and the reversed gradient above the clouds be caused in 
this way. 
