lly stimulated.
Sexual life begins with puberty, and, in the female, ends at about the
age of forty-five years, the period known as the _menopause_, or _turn
of life_. At this period, according to the plainest indications of
nature, all functional activity should cease. If this law is
disregarded, disease, premature decay, possibly local degenerations,
will be sure to result. Nature cannot be abused with impunity.

The generative power of the male is retained somewhat longer than that
of the female, and by stimulation may be indulged at quite an advanced
age, but only at the expense of shortening life, and running the risk
of sudden death. Says Parise, "One of the most important pieces of
information which a man in years can attain is 'to learn to become old
betimes,' if he wishes to attain old age. Cicero, we are told, was asked
if he still indulged in the pleasures of love. 'Heaven forbid,' replied
he, 'I have forsworn it as I would a savage and a furious master.'"

Some learned physicians place the proper limit of man's functional
activity at fifty years, if he would not render himself guilty of
shortening his days by sensuality. Other reasons for this course will
appear hereafter.

When the passions have been indulged, and their diminishing vigor
stimulated, a horrid disease, _satyriasis_, not infrequently seizes
upon the imprudent individual, and drives him to the perpetration of
the most loathsome crimes and excesses. Passions cultivated and
encouraged by gratification through life will thus sometimes assert
a total supremacy in old age.

Marriage.--The scope and plan of this work will allow of but the
briefest possible consideration of this subject upon which volumes have
been written, much to no purpose other than the multiplication of books.
We shall devote no space to consideration of the origin of the
institution, its expediency, or varied relations, as these topics are
foreign to the character of this work.

The primary object of marriage was, undoubtedly, the preservation of
the race, though there are other objects which, under special
circumstances, may become paramount even to this. These latter we
cannot consider, as only the relations of the reproductive functions
in marriage come properly within our province.

The first physiological question to be considered is concerning the
proper age for marriage.

Time to Marry.--Physiology fixes with accuracy the earliest period at
which marriage is admi