401 



DEAF AND DUMB, CENSUS OF THE. 



DEAF AND DUMB, CENSUS OF THE. 



402 



nature of the inquiries to be made. The science of statistics has still 

 much to do for the deaf and dumb, but the inferences from topo- 

 graphical causes must always be faulty in accounting for the prevalence 

 of the malady. Mention has been made of some anomalies which they 

 cannot explain ; they cannot account for the discrepancies between the 

 neighbouring counties of Monmouth and Hereford, between Hunting- 

 donshire and Worcestershire; they cannot show why the healthier 

 province of Denmark, the island of Bomholm, should have more than 

 double the proportion of deaf and dumb that are found in Laaland and 

 Falster, which are considered the unhealthiest parts of the kingdom ; 

 nor why, generally, there are proportionably fewer deaf and dumb to 



be found in towns than in those resorts of health which citizens usually 

 seek for their salubriousness, namely, the sea-coasts, the rural, and the 

 mountainous districts. Some additional light will be thrown on this 

 part of the subject in the article DEAF AND DUMB, VITAL STATISTICS or, 

 and some of the causes which produce and perpetuate deafness, inde- 

 pendent of climate and locality, will therein be considered. 



The following table is drawn from the census returns for 1851, 

 reference being made ?o the pages in which detailed information will be 

 found respecting each county ; the portion referring to Ireland is taken 

 from the report of the commissioners ; special attention will be directed 

 to a few points in it, chiefly in the words of the registrar-general : 



NUMBER AND AGES OP MALES AND FEMALES RETURNED AS DEAF AND DUMB. 





The aggregate number of the deaf and dumb would be increased by 

 a considerable addition to the column " under 5 years," but for the 

 difficulty of ascertaining the existence of deafness, and consequent 

 dumbness, in the early years of life, and the natural indisposition of 

 parents to form a painful conclusion on the subject while the slightest 

 grounds for doubt exist. A rough estimate of the omissions from this 

 cause may be made by assuming the deaf mutes under 5 years of age 

 to bear the same proportion to the general population of the same age 

 as the deaf and dumb aged 5 years and upwards bear to the residue of 

 the population. Under this assumption, the number returned under 

 5 years would be 1801 deaf mutes, instead of 560. In Ireland it U 



ARTS AND SCI. DIV. VOL. III. 



assumed on similar grounds that the number returned under the first 

 quinquennial period should be 492 instead of 227. Under this hypo- 

 thesis the proportion of deaf and dumb in the United Kingdom would 

 be increased from 1:15UO to 1:1460. 



In Great Britain the greatest number was returned between the ages 

 of 5 and 15, then between 15 and 30; after 50 there is a very sensible 

 diminution, showing that the deaf and dumb are not, like the blind, 

 long-lived. In Ireland the greatest number was returned between the 

 ages of 15 and 30, with a similar diminution after 50. Of the 21,487 

 blind persons in Great Britain, only 2929, or less than 14 per cent., are 

 under 20 years of age, a circumstance tending to show that cases pf 



