At the age of 14, the menses, in virgins, begin to flow; then they are
capable of conceiving, and continue generally until 44, when they cease
bearing, unless their bodies are strong and healthful, which sometimes
enables them to bear at 65. But many times the menses proceed from some
violence done to nature, or some morbific matter, which often proves
fatal. And, hence, men who are desirous of issue ought to marry a woman
within the age aforesaid, or blame themselves if they meet with
disappointment; though, if an old man, if not worn out with diseases and
incontinency, marry a brisk, lively maiden, there is hope of him having
children to 70 or 80 years.

Hippocrates says, that a youth of 15, or between that and 17, having
much vital strength, is capable of begetting children; and also that the
force of the procreating matter increases till 45, 50, and 55, and then
begins to flag; the seed, by degrees, becoming unfruitful, the natural
spirits being extinguished, and the humours dried up. Thus, in general,
but as to individuals, it often falls out otherwise. Nay, it is
reported by a credible author, that in Swedland, a man was married at
100 years of age to a girl of 30 years, and had many children by her;
but his countenance was so fresh, that those who knew him not, imagined
him not to exceed 50. And in Campania, where the air is clear and
temperate, men of 80 marry young virgins, and have children by them;
which shows that age in them does not hinder procreation, unless they be
exhausted in their youths and their yards be shrivelled up.

If any would know why a woman is sooner barren than a man, they may be
assured that the natural heat, which is the cause of generation, is more
predominant in the man than in the woman; for since a woman is more
moist than a man, as her monthly purgations demonstrate, as also the