At the close of the war he resigned his commission in the army and wishing active service accepted the appointment first of acting and later as full agent for settling tlie northern boundary of the United States under the 6th and 7th articles of tl;c treaty of Ghent. Until 1828 his summers were occupied in command of the detachment on the boundar}', there he commenced the formation of his afterwards famous collection of minerals. The long co'd winters of the north preventing active operations he p-.i-^ied in New Y^irk, Tloston, riiilailclphia and WaslunLrtoi!. ;ihvay3 studious but not neglectful of the plea.-;urcs of societj-. He marrinl li2ih De-

626 HISTORY OF THE COUNTY OF A\T.STCH ESTER.

cember,lS33. Julia, eldest daughter of Maturin Livingston of Staatsburg. N. Y. and from henceforth devoted himself to his books and scientilic i)ursu'its. ' Fur forty years w>i3 President of the Society of Natural History; was a member of a great number of scientific societies in tliis country and throughout Europe, w^s trustee in many institutions, vestrymau in Trinity church, &c., &c. After a long and useful life he died 12 February 1S75, in hi's 83th year at the same tim^ with his brothers, Henry and Edward, all of whom were buried on the same di-- from Trinity church. The beautiful building could not contain one-fourth o'f tbose who assembled on the 16th of February to pav the last lionors to the brothers Delafield. Major Delafield had issue four chOdren, of whom two sons and one daughter survived him.