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 syphilis; affecting the nerve, paralysis, convulsions, sunstroke, congestion of brain, and disease of nervous system; and affecting brain center, hydrocephalus and epilepsy. Among unclassified causes are also adduced neuralgia, childbirth, accident, medicine, heat, rheumatism, head-ache, fright or shock, overwork, lightning, diarrhea, chicken-pox, operation, and other causes.
[21] Proceedings of National Conference of Charities and Corrections, 1906, p. 250; Ceremonies of Laying of Corner Stone of Rhode Island School, 1907, p. 27.
[22] There are no general or organized movements on foot for the prevention of deafness as there are for the prevention of blindness. This is perhaps chiefly because there are believed to be nothing like so many preventable cases of the one as of the other, so much of blindness being due to diseases that might have been avoided without great difficulty, and to accidents and other injuries to the eye.
[23] It has been estimated that three-fourths of deafness from primary ear diseases, and one-half from infectious diseases, is preventable. See Proceedings of International Otological Congress, loc. cit.; Volta Review, xiv., 1912, pp. 251, 348.
[24] Proceedings, 1903, p. 1036.
[25] Volta Review, xv., 1913, p. 136. See also ibid., v., 1903, p. 415; Outlook, civ., 1913, p. 997.
[26] See Medical and Surgical Monitor, vii., 1904, p. 47; New York Medical Journal, lxxxiii., 1906, p. 816; Annals, lv., 1910, p. 192; Volta Review, xiii., 1911, p. 332.
[27] The possibilities, for instance, in the use of antitoxins and vaccines in certain diseases are just beginning to be known, and some results as affect deafness may be expected from such operations.
[28] In 1909 a special committee in regard to the prevention of deafness was created by the Otological Section of the American Medical Association, and in 1910 both by the American Laryngological, Rhinological and Otological Society and by the American Otological Society. See Laryngoscope, xx., 1910, pp. 596-665; Volta Review, xii., 1910, pp. 267, 545.
[29] Laws, 1906, ch. 502.
[30] On the possibilities of the prevention of adventitious deafness, see Dr. J. K. Love, "Deaf-Mutism", 1896; Archives of Otology, xxiv., 1895, p. 50; Journal of American Medical Association, liii., 1909, p. 89; New York Medical Journal, l., 1889, p. 205; lxxxix., 1909, p. 1007; xcv., 1912, p. 1189; New York State Journal of Medicine, xii., 1912, p. 690ff.; Maryland Medical Journal, lv., 1912, p. 33; Pediatrics, xxiv., 1912, p. 335; Popular Science Monthly, xlii., 1892, p. 211; "Progress in Amelioration of Certain Forms of Deafness and Impaired Hearing," Proceedings of American Association to Promote the Teaching of Speech to the Deaf, iv., 1894; Annals, xxxiv., 1889, p. 199; lvi., 1911, p. 211; lviii., 1913, p. 131; Volta Review, xii., 1910, p. 143; xv., 1913, p. 303; New York Times, April 6, 1913; Public School Health Bulletin, Eyes and Ears, by Superintendent of Public Instruction of North Carolina, 1910.
[31] Census Reports, 1880. Report on Defective, Dependent and Delinquent Classes of the Population of the United States, 1888, p. 402ff.; Census Reports, 1890. Report on Insane, Feeble-minded, Deaf and Dumb and Blind, 1895, pp. 108ff., 648; Special Reports, 1906, p. 122.
[32] Ibid.
[33] Probably with the "fevers" the proportion would be larger.
[34] Less than 0.7 per cent.
[35] Probably included with certain of the suppurative diseases.
[36] Not a large number of schools, it is greatly to be regretted, give, regularly and over an extended period of time, such information in statistical form and upon the same basis from year to year.
[37] Total attendance.
[38] These tables are based upon statistics given in the reports of the schools, and given in Annals, vi., 1854, p. 237; xv., 1870, p. 113; xvii., 1872, p. 167.
[39] One case reported.
[40] Letters of inquiry as to whether or not "total" deafness appeared to be decreasing were sent by the writer to the professors of diseases of the ear of the medical schools of Johns Hopkins University, University of Pennsylvania, Columbia University, Cornell University, Harvard University, University of Chicago, Northwestern University, University of Michigan, and the Jefferson Medical College of Philadelphia. The opinion of four of these is that such deafness is clearly decreasing; of three that little or no decrease is apparent; while by two no opinion can be vouched yet. The greatest encouragement is found in respect to treatment for middle ear affections and infections from fevers. By Dr. S. MacCuen Smith, of the Jefferson Medical College, it is believed that there is a decrease, "largely due to the fact that not only the general medical profession, but the public at large, are recognizing the importance of having the minor aural lesions promptly and properly cared for. This being the case, it is no longer possible for children in the public schools to continue their studies when suffering from diseased tonsils and enlarged adenoid vegetations. From this cause alone, many cases of impairment of hearing which usually occur later in life will be prevented in the future". By Dr. E. A. Crockett, of Harvard University, it is believed that, although there is a larger amount of deafness from measles, there is less, not only from scarlet fever, but also from chronic suppurations, from adenoid and throat troubles in general, and even from meningitis, owing to the use of serums. Regarding his own observations, within a period of twenty-five years "the number of extremely deaf persons and deaf-mutes has very materially diminished".
[41] Hereditary deafness is sometimes of a kind that manifests itself some years after birth, often with certain relatives similarly affected. This is especially true of catarrhal and middle ear affections, though their results may more often be partial rather than total deafness.
[42] In a part of such deafness, and also in a portion of that occurring shortly after birth, the cause is said to be syphilis. See Proceedings of International Otological Congress, ix., 1913, p. 49; Volta Review, xiv., 1912, p. 348; xv., 1913, p. 209.
[43] Special Reports, pp. 125, 236. There were 3,341 who failed to answer, and if all had made reply, our percentage would probably be higher yet.
[44] P. 108.
[45] In the Louisiana School 10 per cent of the pupils are said to have parents who were blood relatives; in the Illinois, 5 per cent; and in the Kansas, from 5 to 5.5 per cent. Report of Louisiana School, 1906, p. 17. See also Transactions of American Medical Association, xi., 1858, pp. 321-425; Proceedings of Conference of Principals, iii., 1876, p. 204; Annals, xxii., 1877, p. 242.
[46] On this subject, see Francis Galton. "Natural Inheritance", 1889, p. 132ff. See also G. B. L. Arner, "Consanguineous Marriages", 1908, p. 65ff.; C. B. Davenport, "Heredity in Relation to Eugenics", 1911, p. 124ff.
[47] Special Reports, pp. 128, 235, and passim.
[48] These proportions are further indicated in the succeeding section.
[49] Special Reports, p. 135ff.
[50] Report, 1908, p. 31.
[51] Out of 107 children born to former pupils of the Minnesota School up to 1892, 2, or 1.9 per cent, were deaf. Report, 1892, p. 39. Out of 811 children born to former pupils of the American School up to 1891, 105, or 12.9 per cent, were deaf. Report, 1891, p. 20.
[52] The study had been originally planned by Dr. F. H. Wines for the International Record of Charities and Corrections. See issue for October, 1888. The work was published by the Volta Bureau. For a discussion of the results, see Association Review, ii., 1900, p. 178; Publications of American Statistical Association, vi., 1899, p. 353; Biometrika (London), iv., 1904-5, p. 465. See also charts in current numbers of Volta Review.
[53] From the total number of marriages, 974 were deducted, being cases concerning the offspring of which no information could be obtained, and also 434 cases where there were no offspring.
[54] From p. 134. It has also been computed by Dr. Fay from his data that of 5,455 married deaf persons, 300, or 5.5 per cent, have deaf offspring. Annals, lii., 1907, p. 253.
[55] The proportions for the general population are hardly over 0.3 per cent and 0.05 per cent respectively.
[56] The proportion of the married deaf who are married to deaf partners is found by Dr. Fay to be 72.5 per cent, and of those married to hearing partners, 20 per cent, there being no information for the remaining 7.5 per cent. The census returns, however, give the respective proportions as 51.3 per cent and 48.7 per cent.
[57] See Proceedings of National Conference of Charities and Corrections, 1879, p. 214; A. G. Bell, "The Formation of a Deaf Variety of the Human Race", Memoirs, 1883, ii., part 4, p. 177; Proceedings of Conference of Principals, i., 1868, p. 91; v., 1884, p. 205; A. G. Bell, "Marriage, an Address to the Deaf", 1898; Evidence before the Royal Commission on the Deaf, etc., 1892, ii., pp. 74-129; Annals, xxix., 1884, pp. 32, 72; xxx., 1885, p. 155; xxxiii., 1888, pp. 37, 206; Popular Science Monthly, xvii., 1885, p. 15; Science, Aug., 1890, to March, 1891 (xvi., xvii.); Arena, xii., 1895, p. 130; Association Review, x., 1908, p. 166; Volta Review, xiv., 1912, p. 184; Proceedings of Reunion of Alumni of Wisconsin School for the Deaf, vi., 1891, p. 46; National Association of the Deaf, iv., 1893, p. 112; ix., 1910, p. 69; Report of Board of Charities of New York, 1911, i., p. 150.
[58] No statutory action seems ever to have been taken in the matter. In Connecticut, however, in 1895 when a law (Laws, ch. 325) was enacted forbidding the marriage of the feeble-minded and epileptic, a provision respecting the congenitally deaf and blind came near being included. Annals, xl., 1895, p. 310.
[59] Census Reports, 1880. Report on Defective, Dependent and Delinquent Classes of the Population of the United States, 1888, p. 402ff.; Census Reports, 1890. Report on Insane, Feeble-minded, Deaf and Dumb and Blind, 1895, pp. 108ff., 684; Special Reports, 1906, p. 122. The ages of the deaf were reported less fully in 1880 than in 1890, and less fully in 1890 than in 1900; and if we take the numbers of those whose ages were reported in these three censuses, we have the following table, showing the proportion of the congenitally deaf.
THE CONGENITALLY DEAF ACCORDING TO NUMBERS IN WHICH AGE WAS REPORTED
| Number Whose Age Was Reported | Congenitally Deaf | Per Cent | |
| 1880 | 22,473 | 12,155 | 54.7 |
| 1890 | 37,204 | 16,866 | 45.8 |
| 1900 | 35,479 | 12,609 | 35.3 |
If we assume that the proportion of the congenitally deaf to all the deaf in each census was the same that it was among the cases in which the age of the occurrence of deafness was reported, we have this table to show the number of the congenitally deaf and the ratio of the deaf among the population.
THE CONGENITALLY DEAF ACCORDING TO NUMBERS ASSUMED
| Assumed Number of Congenitally Deaf | Ratio Per Million of Population | |
| 1880 | 18,531 | 369 |
| 1890 | 18,375 | 293 |
| 1900 | 13,286 | 175 |
These tables are taken from Annals, li., 1906, p. 487.
[60] In the three schools where an increase in congenital deafness appears to be found, namely, those of Michigan, Wisconsin and Ohio, a partial explanation probably lies in the fact that in these states a number of day schools have been created of late years, which are not likely to draw congenitally deaf pupils to the extent that the institutions do, thus leaving a larger proportion for the latter. See also E. A. Fay, op. cit., p. 125.