Were we ssked what wa« probably the mid-winter
temperature of our island 11,700 years ago. when the
winter solstice was in aphelion, we could not tell
unless we knew the temperature of space. Again,
without a knowledge of the temperature of space, it
could not be ascertaineil how much the temperature
of the Nortii Atlantic and the air over it were aSected
by the Gulf Stream. We can determine the quantity
of heat conveyed into the Atlantic by the stream, and
compare it with the amount received by that area
directly from the sun, but this alone does not enable
us to say how much the temperature ia rained by the
heat conveyed. We know that the basin of the North
Atlantic receives from the Gulf Stream a quantity of
heat equal to about one-fourth that received from the




TEMPERATURE OF SPACE. 2S9

3im, but unless we know the temperature of space
we cannot say how mucli thia one-fourth raises the
temperature of the Atlantic. Suppose 56° to be the
temperature of that ocean; thia is 617° of absolute
temperature which is derived from three sourciss, viz. :
(1) direct heat from the aun, (2) heat from the Golf
Stream, and (3) heat from the stars. Now, unless we
know what proportion the heat of the stars beaj-s to
that of the sun. wo have no meaos of knowing how
much of the 517° is due to the stars, and how much to
the sun or to the Gulf Stream.
