In Google books --
bio of Ethelbert Patterson Oliphant, 1803-84, in Biographical and historical catalogue of Washington and Jefferson college ... By Washington and Jefferson College (Washington, Pa.), 1889.
... born Fayette County, Pa., Oct. 4, 1803 ... practiced law Uniontown, Pa., Springfield, Ill., Beaver, Pa., adjutant regiment Black Hawk war of '32, prosecuting atty of Fayette County, Pa., Pennsylvania Legislature, '30-31; clerk in Law Department, Harrisburg, '33-36; Associate Judge Supreme Court, Washington Territory, '61-65; clerk Interior Department, '66-84; married May 13, '40, Elizabeth C. Howe, daughter of Jonas Howe; died May 8, '84. Lawyer.
The Collected Works of Abraham Lincoln, Volume 4 By Abraham Lincoln
Memorandum: Appointment of Ethelbert P. Oliphant c. April 5, 1861, p 332
Note 332n: Oliphant to Lincoln, July 28, 1859, recalled that "...our first acquaintance and interview, took place in the Spring of 1832 at 'Salem'. ..." fratres miles in Black Hawk War ... asked for appointment in swamp land division of the General Land Office, "Allow me modestly to remark, that I think I am deserving of something better ..." L. appointment him associate justice of SC in Wash Territory