411 



DEAF AND DfMB, VITAL STATISTICS OF. 



DEAF AND DUMB, VITAL STATISTICS OF. 411 



das* deafness, both in iU congenital and acquired fomu, iuy be 

 placed. The oooditioo of thing* nscasury to bring about inch result 

 may be aided and encouraged by wise legislative enactment*, by in- 

 unnil knowledge, and a willingness to observe the Uw which govern 

 and regulate life and health. When it U generally admitted that 

 obedience to lh*o law* U favourable to soundness of body and mind, 

 and that a disregard of them brings its own punishment in the form of 

 dims*, and early death, we may hope that many of the affliction* 

 under which mankind labour will paw away or suffer diminution. 



TABLE IX. 



SHOWIX.I TBt XVKUB OF CmUWKX BOW IX BACH FAMILY, AXI> TUI XBJISES 



or rmx CHIUDIEX Diur urn Dem. 



The principal ascertained causes of congenital deafness are heredi- 

 tary transmission, consanguine marriages, feebleness of constitution in 

 the parents, scrofula, the influence of locality, and the ill-health of or 

 accident to the mother during pregnancy. The experience of our 

 institutions at home and abroad, and the researches and opinions of 

 scientific men have accumulated evidence on all these causes which 

 entitles them to separate consideration. The results of such researches 

 and opinions will be given, but only to such an extent as can be borne 

 out by the confirmatory experience of the writer. Cases similar to those 

 to be adduced are of constant occurrence in all institutions for the deaf 

 and dumb, and might be multiplied to an almost indefinite extent The 

 physical history of deafness has attracted much attention during recent 

 yean, and the surmises of a quarter of a century ago, have now in 

 many instances, become established facts. 



Several cases of the transmission of deafness through three genera- 

 tion* are known to the writer of this article ; evidence of a similar 

 nature from other sources is proof sufficient that one of the main 

 causes of deafness is Hereditary Trantmution. " It has been clearly 

 ascertained," says Mr. Harvey, ' On the Ear,' " that the most common 

 cause is a strumous and delicate habit of the body, generally hered- 

 itary." An important table is given in the census returns for Ireland, 

 " showing the result of hereditary predisposition, or family peculiarity 

 in the production of congenital muteistn. From its arrangement we 

 learn that in 329 instances, numbering 471 persons born in families 

 some of the previous members or collateral branches of which were 

 mute, 240 persons were born deaf and dumb where the disease appeared 

 to come from the father's side ; whereas in the other division, where 

 the affection was transmitted through the female line the number 

 amounted but to 222. Among the examples which are given illustrative 

 of this table we find the following : In cases of single congenital 

 muteism, where the relatives were also deaf and dumb, there were by 

 the father's side in two instances an uncle and an aunt, in one case 

 two grandaunU, in one instance two aunts, in one case an aunt ami a 

 cousin, in another case two nieces and a cousin, in another instance 

 six cousins ; in three case* there were four cousins ; in eleven instances, 

 three cousins ; and in nine cases two cousins, all deaf-mutes. Where 

 two of the family were affected with congenital deaf-dumbness, in two 

 instances four cousins were in a similar condition, in two cases three 

 cousin* were deaf and dumb, and in four instances two cousins were 

 thus afflicted. Wlu.Ti- three cases of congenital deaf-dumbness occurred 

 in the came family, in one case the great-grandfather bad been deaf 

 and dumb, in two instance* two grand-uncles had likewise been deaf- 

 mute*, and in five case* two cousins were in a similar condition. 



Where the relationship came by the mother's side, there were in 

 cases of single congenital muteism, one instance of a niece and one 

 cousin ; eight cases where three cousins were deaf and dumb ; and 



fourteen instances where two cousins were thus affected. In cases of 

 two mutes in the same family, we find that in one case 'two aunts were 

 also deaf and dumb, in one case three cousins, and in four case* two 

 cousin* laboured under tli- like defect Where three mutes occurred 

 in the same family, in one instance an uncle and an aunt, and in 

 another a half-uncle and an aunt, were deaf and dumb; and two cases 

 presented two cousins also deaf and dumb." The thirty-fourth Report 

 of the Glasgow Institution (1855) gives cases similar in character to 

 the above, from the records of that institution, and every school of the 

 kind could supply facts bearing on the hereditary transmission of deaf- 

 dumbness. 



C'lXtanyuiiit Uarriaget are, next to hereditary transmission, perhapx 

 the most fertile source of deafness. Every institution in the kingdom 

 bean witness to this fact in the numerous cases of pupils who are the 

 offspring of first cousins. And deafness i* not the only evil result ; 

 idiotcy, blindness, feebleness of frame, insanity, the death of children 

 in early life, and various physical imperfections, such as club-foot, hare- 

 lip, and spinal deformities are too often the result of such marriages. 

 Mr. Buxton says, " In an inquiry which I made sometime ago, from a 

 large number of persons, I found that about every tenth case of 

 ness resulted from the marriage of cousins ;" and Dr. Peet, of t!. 

 York Institution, confirms this ratio ; the writer's experience is very 

 similar, and has extended to other mental and physical defects, as well 

 as to deafness, as a common result of such marriages. The Irish Com- 

 missioners report on this branch of their inquiry as follows : " Among 

 the predisposing causes of hereditary disease, the too close consan- 

 guinity of parents has long been looked upon as paramount, anil mii- 

 sequently, an inquiry was made as to its probable effect in producing 

 iinbness. Returns of this nature must be expected to be 

 deficient ; still, 170 instances were recorded, in which the parents were 

 related in the degrees of first, second, or third cousins. The result of 

 these intermarriages was 109 cases of owe in a family deaf and dumb, 

 of which ninety-four were congenital and five acquired ; three were 

 dumb only, and seven dumb and idiotic. Thirty-seven cases of con- 

 genital and one of acquired deaf -dumbness occurred, where two of 

 the family were affected, including four out of the fifteen cases of 

 twins already specified. Of the remainder, seventeen instances oc- 

 curred in which three of the same family; and three where four in 

 the one family were deaf and dumb. In one of the instances where lir 

 in the family were deaf and dumb, and in the cases of both seven and 

 eight deaf and dumb in families, the parents were also nearly con- 

 nected. These numbers include, not merely the living upon the 

 night of the 30th of March (when the census was taken), but all the 

 children living or dead, born deaf and dumb of the same parents." 



A writer in the 'British Quarterly Review' (No. LVII.) has taken up 

 this subject in its many bearings, and as our own experience confirms 

 his statements, we do not hesitate to quote them : " Popular opinion 

 and scientific induction equally lead to the impression, that although 

 one marriage between near relatives may be unattended liy <\il ruti- 

 sequences immediately perceptible, yet it is very rare that the second 

 or third is so innocent. There usually arises amongst the children 

 resulting from such unions a tendency to disorders, functional or 

 organic, of the" nervous system, or of the nutritive organs, tending in 

 the former case to unsoundness of mind, and in the latter to con- 

 ditions bordering on scrofula, or an allied affection. M. Devay found 

 in the children proceeding from 121 consanguine marriages, twenty-two 

 cases of sterility (actual and virtual), twenty-seven cases of various defor- 

 mities, and two deaf-mutes. Dr. Boinet knew five idiots in five 

 different families sprung from this sort of marriage. A celebrated 

 lawyer, married to a cousin, lost three children from hydrocephalus. 

 A manufacturer at Lyon, similarly married, had fourteen children; 

 eight died of convulsions at an early age ; only one survived ; the 

 remainder died of scrofulous affections. In our own circle of acquaint- 

 ance we know several families where there is an idiot child, or where 

 several of the children have the most strongly-marked nervous pecu- 

 liarities, to which the parents and the ancestry were strangers, and for 

 which there seemed to be no plausible reason, except that their parents 

 were cousins, and that the families had been in the habit of inter- 

 marrying." The writer of this article has, for. several reasons, preferred 

 giving the above extracts to detailing similar cases which have come 

 within his own observation, but he is acquainted with more than fifty 

 instances in which cousins have intermarried, and whose children have 

 been visited with one or more of the evils above alluded to ; he, there- 

 fore, regards such marriages as the transgression of a natural law, 

 which is followed by its own punishment. 



The records of every institution for the deaf and dumb, and the 

 observations of individuals who have applied themselves to this in- 

 quiry, show that constitutional feebleness in one or both parents is a 

 cause of deaf-muteism. In every institution there is a larger pro- 

 portion of orphans and half-orphans than would be found among the 

 children in an ordinary school, and also a larger proportion of p 

 lalxmring under some physical infirmity. On one of these points, the 

 i ork Report, to whf.'h we have before referred says, " We have 

 noticed that a large proportion of our pupils, perhaps one-fifth, had 

 lost one or both parents before they came to school ; but we have no 

 data to show that this is a larger proportion of orphans and half- 

 orphans than would lie found on an average in a promiscuous collec- 

 tion of children who wi-re not deaf." To this testimony it may be added, 



