As a member of the Senate committee on military affairs during the World War he took part in investigations which resulted in a reorganization of the ordnance and quartermaster departments as well as the aircraft production board.
In 1860 he was made quartermaster-general, with the rank of brigadiergeneral.
The pay of his rank was small, and his appointment on the quartermaster-general's staff made it necessary to keep two horses, so that he had to write mathematical school-books in his spare time to eke out his resources.
Wilkinson then resigned (March 1778) his newly-acquired commission, but later re-entered the service in the quartermaster, He died in London on the 19th of general's department, and was clothier-general from July 1779 to March 1781.
After the Mexican war he served in the West, in Florida and elsewhere; was married in 1850 to Miss Almira Russell of St Louis; became first lieutenant in 1853, and assistant-quartermaster with the rank of captain in 1855.