178 
HAROLD’S DISCUSSIONS. 
yields to the sun not only in gravitation and the mat¬ 
ter of heat and light, but probably for electricity. 
THE MOON. 
The moon, being distant only about thirty times 
the earth’s diameter, appears to us about the same 
size as the sun, but, in fact, its diameter is only two 
thousand one hundred and sixty miles, and it would 
take eighty-one moons to equal our earth. 
When the moon is on the same side of our globe 
as the sun we can not see it, for the illuminated part 
is turned away from us. That is new moon. As the 
moon moves east, we see the illuminated part more 
and more, first as a narrow crescent in the west, 
gradually increasing until we see half of the illumi¬ 
nated part in the south, and then all of it as the full 
moon in the east. Passing through the “gibbous” 
last quarter and final crescent stages back to the new 
moon, it completes its course in twenty-nine days, 
twelve hours, forty-four minutes, three seconds. This 
is about two days more than is required for a revolu¬ 
tion. As the earth moves forward in its orbit, the 
moon must make more than one revolution in order 
to get back to the same position in relation to the sun. 
The face of the moon has attracted so much at¬ 
tention that the “ man in the moon ” has become 
famous. But is it a man ? Observe the face, if pos¬ 
sible, with an opera-glass. About the first quarter we 
can see bright spots, and near them corresponding 
dark ones, as if they were mountain peaks on which 
the sun is refiected and adjacent valleys in the shadow 
