Venus . . . . Friday.
Saturn . . . . Saturday.

That is to say, we have the planets in the order in which they
were supposed to rule over the days of the week. This is perhaps,
not so surprising, because it seems probable that, each day being
first divided into twenty-four hours, it was assumed that the planets
ruled for one hour in turn, in the order first mentioned above.
Each day was then named after the planet which ruled during its first hour.
It will be found that if we start with the Sun and write down every
twenty-fourth planet, the result is exactly the same as if we write
down every third. But Mr OLD points out further, doing so by means
of a diagram which seems to be rather cumbersome that if we start
with Saturn in the first place, and write down every fifth planet,
and then for each planet substitute the metal over which it was
supposed to rule, we then have these metals arranged in descending
order of atomic weights, thus:--

Saturn . . . Lead (=207).
Mercury . . . Mercury (=200).
Sun . . . . Gold (=197).
Jupiter . . . Tin (=119).
Moon . . . . Silver (=108).
Venus . . Copper (=64).
Mars . . . . Iron (=56).


Similarly we can, starting from any one of these orders, pass to the
other two. The fact is a very surprising one, because the ancients
could not possibly have been acquainted with the atomic weights of