pulation. From our knowledge concerning adventitious deafness, the
probabilities are that, if anything, it is decreasing; while the
evidence as to congenital deafness is that it is decreasing. It is
likely, then, that deafness in general is tending to decrease; and we
are thus justified in believing that the number of the deaf will in time
become less.

FOOTNOTES:

[15] Moreover, later censuses are probably taken more thoroughly than
former, with a consequent discovery of a larger number of the deaf;
while at the same time greater care is employed in preparing the later
censuses, with the more rigorous elimination of doubtful cases, all in
some measure, however, tending to even up the differences. On the
difficulty of making comparisons of the censuses of the deaf, see
Special Reports, pp. 66-69; _Annals_, li., 1906, p. 487.

[16] _Ibid._

[17] Deafness has also been divided into three classes: adventitious
deafness, congenital or hereditary deafness, and infantile or sporadic
congenital deafness, the last class including many cases where there are
other antecedent defects, mental or physical, or where the deafness
occurred shortly after birth with the exact cause not definitely
determined. See Proceedings of International Otological Congress, ix.,
1913, p. 49; _Volta Review_, xiv., 1912, p. 348; xv., 1913, p. 209.

[18] Of the cases usually ascribed to accidents, as falls, blows and the
like, the probabilities are that a large part are really to be
attributed to some other cause. Deafness is not often likely to result
from such occurrences.

[19] See Proceedings of International Otological Congress, ix., 1913, p.
49; _Volta Review_, xiv., 1912, p. 348.

[20] Special Reports, pp. 110, 122, 124. See also _Annals_, xxxiii.,
1888, p. 199; lii., 1907, p. 168. In the table are given only the
specified causes that represent at least 0.7 per cent of the total
amount of deafness. In respect to external ear trouble, impacted cerumen
is usually found to result from water in the ear, or wax in the ear.
Other diseases of the middle ear of suppurative character are
diphtheria, pneumonia, erysipelas, smallpox, tonsilitis, teething,
bronchitis, and consumption. Other non-suppurative diseases of the
middle ear are whooping cough, scrofula, exposure and cold, disease of
the throat, thickening of eardrum, croup, etc. Of the internal ear,
other causes affecting the labyrinth are malformation, noise and
concussion, mumps, and sy