son of the forcible injection of the seed.

Also, if the stones have received any hurt, so that they cannot exercise
the proper gift in producing seed, or if they be oppressed with an
inflammation, tumour, wound or ulcer, or drawn up within the belly, and
not appearing outwardly.

Also, a man may be barren by reason of the defect of seed, as first, if
he cast forth no seed at all, or less in substance than is needful. Or,
secondly, if the seed be vicious, or unfit for generation; as on the one
side, it happens in bodies that are gross and fat, the matter of it
being defective; and on the other side, too much leanness, or continual
wasting or consumption of the body, destroys seed; nature turning all
the matter and substance thereof into the nutriment of the body.

Too frequent copulation is also one great cause of barrenness in men;
for it attracteth the seminal moisture from the stones, before it is
sufficiently prepared and concocted. So if any one, by daily
copulation, do exhaust and draw out all their moisture of the seed, then
do the stones draw the moist humours from the superior veins unto
themselves; and so, having but a little blood in them, they are forced
of necessity to cast it out raw and unconcocted, and thus the stones are
violently deprived of the moisture of their veins, and the superior
veins, and all the other parts of the body, of their vital spirits;
therefore it is no wonder that those who use immoderate copulation are
very weak in their bodies, seeing their whole body is deprived of the
best and purest blood, and of the spirit, insomuch that many who have
been too much addicted to that pleasure, have killed themselves in the
very act.

Gluttony, drunkenness, and other excesses, do so much hinder men from
fruitfulness, that it makes them unfit for generation.

But among other causes of barrenness of men, this also is one, and makes
them almost of the nature of eunuchs, and that is the incision or the
cutting of the veins behind their ears, which in case of distempers is
oftentimes done; for, according to the opinions of most physicians and
anatomists, the seed flows from the brain by those veins behind the
ears, more than any part of the body. From whence it is very probable,
that the transmission of the seed is hindered by the cutting of the
veins behind the ears, so that it cannot descend to the testicles, or
may come thither very crude and raw.

SECT. III.--_Signs and Causes of Insuffi