of the
interests of society; and in their reduction there will probably be a
greater or less diminution of congenital deafness.

With regard to consanguineous marriages and their effect on deafness we
are on surer ground, so far as may be indicated by statistical data.
This question is found in very great measure to be connected with that
of deaf relatives in general. The matter appears to be largely a part of
a law of wide application, namely, that in the blood relationship of
parents the possibilities are intensified of the perpetuation of a
certain strain, which holds true no less with the transmission of
deafness. Consanguineous marriages are perhaps not of sufficiently
frequent occurrence, so far as concerns the effect on deafness, to
require special action; but in the consideration of such marriages in
general, their part in the causation of deafness should have due weight;
and whatever may be said regarding them in other relations, they are to
be avoided if we wish to remove all chances of this kind of deafness
resulting.

The problem of deaf relatives and their connection with congenital
deafness is a very large one. Attention however, has mostly been focused
upon it in relation to the intermarriage of the deaf and its effect upon
their offspring. Indeed, in such unions there has already been more or
less concern, and there has even been question whether it is a wise or
unwise policy to allow the deaf to marry other deaf persons. The deaf,
as we shall discover, not only find their companions for social
intercourse among similar deaf persons, but _a fortiori_ very often seek
such persons for their partners in marriage--in fact, more often than
they do hearing partners, nearly three-fourths of the married deaf being
married to deaf partners.[56] Not only has it been feared that the
offspring of such marriages might likewise be deaf, but there has also
been apprehension lest in their encouragement there might result a deaf
species of the race.[57]

From our discussion, however, we have found that in most of the
marriages of the deaf we have but small reason for disquiet. If deafness
in the parent is really adventitious, there is little possibility of its
passing on to the offspring. When the deafness in the parent is itself
congenital, the situation becomes more serious. If in such case there is
no added risk from the existence of deaf relatives, the likelihood of
transmitting deafness need not always be a matt