640 
Latent Heat . 
[November, 
its way downwards may be seen on the Cape Flats, not far 
from Cape Town. Near the Diocesan College, Rondebosch, 
runs a small stream, known, I believe, as the Little Black 
River. As I walked along the dry bed of the stream I found 
my path continually obstructed by roots, which run right 
across the channel from one bank into the other, and are at a 
height varying from J a foot to 2 feet 6 inches from the 
present bed of the stream. It is clear that these roots can- 
not have got across from one bank to another as the channel 
now is. They must have passed beneath the former bed of 
the stream, and they now remain to show how rapidly the 
stream is cutting its way downwards. 
(To be continued.) 
II. LATENT HEAT. 
By Charles Morris. 
(Concluded from page 533.) 
S QUESTION now arises as to the efficacy of this 
process of equilibration of temperature. In truth 
the differences of sensible heat between the orbs 
and the matter of space are being but very slowly rectified, 
if at all. The principal, and perhaps the only, heat emis- 
sions from the orbs into space, are in the form of radiant 
heat. This is a surface emission from the spheres, and it 
possibly never becomes static heat until it reaches the sur- 
faces of other spheres. The vast volumes of motive energy 
thus poured into space may pass through a completely trans- 
parent medium, and, if so, can have no effeCt in raising the 
temperature of interspheral matter. The spheres tend, in 
this manner, to produce temperature equilibrium among 
themselves, but may fail to affeCt the matter of space. 
The radiated energy is superficial only, and must depend 
for its supply upon a very slow conduction of internal heat 
to the surface, or on a more rapid convection while spheres 
continue liquid or gaseous. In one or the other of these 
modes the internal heat of spheres reaches their surfaces, 
and is thence radiated outwards. There is probably no heat 
conduction through the atmosphere. There is a certain 
