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IV.] Wisdom, the Measurer of Time, i 13

weighed, was lord, not of the sun, but of
the moon ; and to that latter orb we are
indebted for our fundamental standards both
of space and time, as we may easily see,
remembering always that we are dealing with
approximate measures, and " mean," or aver-
age motions. For the position of a heavenly
body is, in general, not the same to an
observer on the earth's surface as it would
be if he were stationed at its centre, which
is the chief point of astronomical reference.
This difference, or parallax, must therefore be
always taken into consideration; and in the case
of the moon, when on the horizon, it is found to
be about * the three hundred and sixtieth part
of the circle of the heavens—that is, a degree ;
and conversely therefore the fundamental mea-
sure of the circle is given by the difference
between the moon's apparent position on rising

* It fulls short by not quite three (circular) minut*as,
or rather less than a seven-thousandth part of the cir-
cumference.
 
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