226 MEMOIRS OP THE NATIONAL ACADEMY OF SCIENCES. 



been furnished in advance of the publication of the census returns by tlie courtesy of General 

 Seaton, General SuiJerintendent of the Census. (See "Science," vol. iii, p. 244; and "American 

 Annals of the Deaf and Dumb," vol. xxix p, 160.) 



4. Table S shows («) the number of schools and institutions for the education of the deaf and 

 dumb in the United States, 18S3; (b) the date of opening of each institution; (c) the number of 

 deaf children under instruction, 1883; and (f?), the total number of pupils that have been received 

 into the institutions. These particulars have been obtained from the "American Annals of the 

 Deaf and Dumb," vol. xxix, pp. 90-1)4. The table also shows (e) the number of deaf children 

 whose parents were deaf-mutes who have been received into the institutions. These particulars 

 have been received directly from the principals or superintendents of the institutions and schools in 

 answer to a circular-letter of inquiry. The total number of such pupils cannot be ascertained from 

 the table as some of the institutions have not yet made returns. 



5. Table T gives an analysis of 215 cases of deaf-mutes whose parents were deaf. 



G. In Table U the total population of the country, the congenitally deaf population, and the 

 deaf-mutes who have both parents deaf, are .classified according to their period of birth, and the 

 number of persons born in each period has been reduced to a percentage of the whole. 



7. Table V contains a tabular statement of the institutions of the world in 1882, showing the 

 methods of instruction employed. This Table is taken from the "American Annals of the Deaf 

 and Dumb," for January, 1883, vol. xxviii, p. 61. 



8. Table W gives a list of those pupils of our institutions for the deaf and dumb who are stated 

 to have deaf parents. The information has been obtained directly from the principals and super- 

 intendents of the institutions in answer to a letter of inquiry. 



9. Table X shows the per capita cost of the education of a deaf child in an American institu- 

 tion. This table was prepared by the principal of the Illinois Institution from materials published 

 in the American Annals of the Deaf and Dumb, and from other materials privately collected and 

 published in the Twenty-first Biennial Eeport of the Illinois Institution (1882), pp. 10-17. 



10. Table T contains a tabular statement concerning the teaching of articulation in the insti- 

 tutions of the United States in May, 1883. The information was obtained by the principal of the 

 Clarke Institution, Northampton, JMass., directly from the principals of the other institutions in' 

 reply to a circular of inquiry. See Appendix B, Sixteenth Annual Keport of the Clarke Institu- 

 tion for Deaf-Mutes, September 1, 1883. 



11. Appendix Z contains an examination of the marriages of the pupils of the American Asy- 

 lum and Illinois Institution by the light of the theory of Probabilities, with the object of determin- 

 ing approximately the proportion of the congenitally deaf who marry congenital deaf-mutes. This 

 investigation has been kindly undertaken by Prof. Simon Newcomb, to whom I am indebted for 

 the results obtained. 



