olly due to misery, but rather to listlessness, due to
discouragement, and acting adversely in many ways.

One notable result of dulness and apathy is to make a person
unattractive to the opposite sex and to be unattracted by them. It
is antagonistic to sexual affection, and the result is a diminution
of offspring. There exists strong evidence that the decay of
population in some parts of South America under the irksome tyranny
of the Jesuits, which crushed what little vivacity the people
possessed, was due to this very cause. One cannot fairly apply the
term "misery" to apathy; I should rather say that strong affections
restrained from marriage by prudential considerations more truly
deserved that name.

EARLY AND LATE MARRIAGES

It is important to obtain a just idea of the relative effects of
early and late marriages. I attempted this in _Hereditary Genius_,
but I think the following is a better estimate. We are unhappily
still deficient in collected data as regards the fertility of the
upper and middle classes at different ages; but the facts collected
by Dr. Matthews Duncan as regards the lower orders will serve our
purpose approximately, by furnishing the required _ratios_, though
not the absolute values. The following are his results,[17] from
returns kept at the Lying-in Hospital of St. Georges-in-the-East:--

Age of Mother
at her Marriage. Average Fertility.
15-19 9.12
20-24 7.92
25-29 6.30
30-34 4.60

The meaning of this Table will be more clearly grasped after a
little modification of its contents. We may consider the fertility
of each group to refer to the medium age of that group, as by writing
17 instead of 15-19, and we may slightly smooth the figures, then
we have--

Age of Mother at her Approximate average
Marriage. Fertility.
17 9.00 = 6 x 1.5
22 7.50 = 5 x 1.5
27 6.00 = 4 x 1.5
32 4.50 = 3 x 1.5

Which shows that the relative fertility of mothers married at the
ages of 17, 22, 27, and 32 respectively is as 6, 5, 4, and 3
approximately.

The increase in population by a habit of early marriages is further
augmented by the greater rapidity with which the generations follow
each other. By the joint effect of these two causes, a large effect
is in time