"Oscar Hanks was born in Gibbonsville (now Watervliet), New York about 1810, the second child and first son of Julius Hanks and a grandson of Colonel Benjamin Hanks; both instrument makers.  Oscar Hanks died in Cincinnati, Ohio in 1883.  He is listed in the Troy, New York directories from 1831 through 1845-46 as a mathematical instrument maker.  He is listed in the Chicago directories 1856-57 and 1860; the Cincinnati directories from 1876 to 1883.  

In the May 21, 1830 issue of the Troy Sentinel (New York), there is an advertisement to the effect that A. (Alpheus) & T. (Truman) Hanks have purchased the establishment of Julius Hanks in Troy and that Julius Hanks will be their agent.  Alpheus was the brother and Truman was the son of Benjamin Hanks.   Then, in the July 1, 1834 issue of the Troy Daily Whig, Oscar Hanks, son of Julius Hanks, advertises that he is the successor to A. & T. Hanks and that he will continue in the same line at the same address."

Reference:  Smart, Charles E.  The Makers Of Surveying Instruments In America Since 1700  Troy, New York:  Regal Art Press.  1962