(_This method is taken from an ancient treatise on Astrology._)
Ascertain from any almanac the day on which a full moon occurs, and
count the number of days from that to the end of the month: you then
multiply the number of days in the month by the number ascertained as
above, and the total will give you the lucky days (subject to a further
test hereafter explained). If the total happens to be, say, 516, the
lucky days of that month would be the 5th and 16th, and if it should be
399—as neither of these figures can be paired—the lucky days from
that total are the 3d and 9th, and the 9th would be considered doubly
lucky, if no tests worked to the contrary.
The unlucky days are determined in precisely the same manner, by
multiplying the number of days in the month by the number which have
passed previous to a full moon.
After working out your list of lucky days in the manner above
described, you must then test them, in order to be sure that there are
no opposing influences. You can do this by calculating the unlucky
days. Should you find that any day of the month which was designated as
lucky came also in the list of unlucky days the latter preponderates
and you must strike it from the lucky list.
This plan of demonstrating lucky and unlucky days is very ancient,
and has been tested to such an extent that it is considered accurate
by most astrologers. In olden times, before the mass of the people
understood much about figures, the professional fortune-tellers
demanded a large fee for computing the lucky days of any month, which
they accomplished in the manner above described.
Lucky marriage days for girls were cast in the same manner, except
that the age of the girl was used as the multiplicator, or multiplier,
instead of the number of days in the month. The result was determined
similarly, and also by a test of the unlucky days. Thus if a girl is
eighteen years old, and thinks of marrying in October, she takes up
an almanac and ascertains the day of the full moon in that month. If
it occurs on the 24th, and there are thirty-one days in the month
this leaves seven for the multiplier. She multiplies this by her age,
eighteen, and the result is 126, which shows that the lucky days for
her marriage in that month are the 12th and 6th, unless they are
destroyed by another test, which is determined as follows. There are
twenty-three days before the 24th, and she must multiply twenty-three
by eighteen, which process gives 414, and shows that the 4th and 14th
are the only unlucky days for her marriage. And as they do not conflict
with the lucky days, the 6th and 12th may be considered as genuine
lucky days for that month, reckoning the moon to be full on the 24th.
In determining her age, she should reckon any period over half a year
as a full and completed year.