130 ECONOMIC PRINCIPLES

but that has been excluded from the present discussion, and
if the drain form no part of the redistribution of labour
among various employments, required when some trades
have a deficient supply while others are overcrowded,
merely transfers the problem of excessive supply to another
class of labour.
The only other mode of reduction in labour supply is
that of a reduced birth-rate or increased death-rate, or a
reduction of the work obtainable from each individual may
take place. Privation may render the members of the class
more liable to attacks of disease, increasing the loss of
working time from that cause, and resulting in earlier death
or incapacity. As stated above, the fall in earnings below
the amount needed to support life on the class standard
does, in practice, lead to some reduction in the amount, or
deterioriation in the quality, of the consumption of what
contributes to physical health and strength, even though
earnings still suffice to provide for some consumption of
luxuries. This reduction of the more essential parts of
consumption reacts on the efficiency of labour, which is also
affected by the moral or intellectual attitude of workmen
in reference to work which they regard as inadequately
remunerated.
In addition to these influences on the working efficiency
of the living, it is necessary to consider the influence of
reduced means on the natural increase of numbers, Though
it may be true that some classes are reckless in regard to
the responsibilities of parentage, and that, in consequence,
their birth-rate shows no response to decreasing prosperity,
the more intelligent members of the wage-earning classes,
perhaps all except the very lowest grades, are influenced
in this respect by adversity. A fall in earnings operates
to retard marriage, since the class standard of family life
cannot be supported on the reduced earnings. How general
this influence is can be seen by comparison of the marriagerate
 in prosperous and dull times. The differences may
be small, but they are real and not negligible. A check
to marriages brings about a reduction in births, thus
checking the supply of labour at the fountain-head. A