OF HEAT FROM THE MOON. 
627 
A further, but probably a less important, cause for the divergence of the heat- and 
light-curves lies in the fact that the moon’s surface to a certain extent “ regularly 
reflects” as well as diffuses light and heat. 
Let R, R' be respectively the light and heat regularly reflected. 
D, D' be respectively the light and heat regularly diffused, unchanged in refran- 
gibility. 
E, E' be respectively the light and heat regularly absorbed and afterwards emitted. 
F, F be respectively the light and heat regularly radiated after more than one 
reflection. 
As long as ^ ie ^ w0 curves be identical, even though R and R' be 
a different function of the elongation from D-f-E-f-F and D'-f-E' + F. But if this rela- 
tion does not hold, which will be the case if for F<F andE' = 0, then the phase- 
curve for R, R' will govern the resulting curve for total light more than it will do that 
for total heat. 
4 p 
MDCCCLXX1II. 
