John Langdon Haydon Down
1828–96
Physician. Studied at the London Hospital; MB 1858; MD 1859; assistant physician, 1859. MRCP 1859; FRCP 1869. Established a private home for mentally handicapped people at Normansfield, Hampton Wick, in 1868. Best known for his recognition of the "Mongol" as a distinct type of idiot; the condition was later known as Down’s syndrome. Changed his surname by deed poll to Langdon-Down.
Source
ODNB.
Bibliography
ODNB: Oxford dictionary of national biography: from the earliest times to the year 2000. (Revised edition.) Edited by H. C. G. Matthew and Brian Harrison. 60 vols. and index. Oxford: Oxford University Press. 2004.


