wife from
the first day she is purged to the fifth, she will conceive a male; but
from the fifth to the eighth a female; and from the eighth to the
twelfth a male again: but after that perhaps neither distinctly, but
both in an hermaphrodite. In a word, they that would be happy in the
fruits of their labour, must observe to use copulation in due distance
of time, not too often nor too seldom, for both are alike hurtful; and
to use it immoderately weakens and wastes the spirits and spoils the
seed. And this much for the first particular.

The second is to let the reader know how the child is formed in the
womb, what accidents it is liable to there, and how nourished and
brought forth. There are various opinions concerning this matter;
therefore, I shall show what the learned say about it.

Man consists of an egg, which is impregnated in the testicles of the
woman, by the more subtle parts of the man's seed; but the forming
faculty and virtue in the seed is a divine gift, it being abundantly
imbued with vital spirit, which gives sap and form to the embryo, so
that all parts and bulk of the body, which is made up in a few months
and gradually formed into the likely figure of a man, do consist in, and
are adumbrated thereby (most sublimely expressed, Psalm cxxxix.: "I will
praise Thee, O Lord, for I am fearfully and wonderfully made.")

Physicians have remarked four different times at which a man is framed
and perfected in the womb; the first after coition, being perfectly
formed in the week if no flux happens, which sometimes falls out
through the slipperiness of the head of the matrix, that slips over like
a rosebud that opens suddenly. The second time of forming is assigned
when nature makes manifest mutation in the conception, so that all the
substance seems congealed, flesh and blood, and happens twelve or
fourteen days after copulation. And though this fleshy mass abounds with
inflamed blood, yet it remains undistinguishable, without form, and may
be called an embryo, and compared to seed sown in the ground, which,
through heat and moisture, grows by degrees to a perfect form in plant
or grain. The third time assigned to make up this fabric is when the
principal parts show themselves plain; as the heart, whence proceed the
arteries, the brain, from which the nerves, like small threads, run
through the whole body; and the liver, which divides the chyle from the
blood, brought to it by the vena porta. The two first ar