Not my family line, just sharing.
The following biographical sketch is typed as it appears in the reference book, the name Isaac Mason was provided by Joseph Reed Williams in a posted reply to this same posting in the Davis Family Forum. Please see the posted reply of Joseph Reed Williams at the following link for more information on this family of Davis.
From the book "HISTORY AND BIOGRAPHY, COUNTIES OF WHITE AND PULASKI INDIANA. Historical and Biographical. Illustrated. Chicago; F. A. Battey & CO., Publishers. 1883."
page 341, Princeton Township, White County, Indiana
I. M. DAVIS is a native of Champaign County, Ohio, born November 6, 1829; is of German, Scotch and Welsh descent, and a son of JOHN and ISABEL (NEWLAND) DAVIS. The Grandfather of MR. DAVIS was stolen when a child by some sailors, and brought to America; he was also a soldier in the Revolutionary War, and that of 1812. The father of MR. DAVIS came to Ohio from Virginia when seventeen years of age, and there remained until the latter was eight years old, when he came to White County, and landed in Prairie Township November 10, 1837, and began settlement just east of where Brookston is now situated, and here he lived until his death, November 10, 1880. I. M. was fourteen years old before he knew anything about school life. The first school he attended was at a round-log schoolhouse that stood near the center of a district that was eight miles square. ALFRED HARRIS was MR. DAVIS' first teacher. MR. DAVIS was married, August 22, 1848, to MISS SARAH A. MAHAN, daughter of JOHN and HESTER MAHAN, of Tippecanoe County. This union had four children born to it, viz.; JOHN W., HESTER A., MARY A. and GEORGE W. The next fall after MR. DAVIS was married, he began life for himself, and moved into an old hut that stood three miles from the old homestead. The first meal in the new home consisted of forage, potatoes and butter, and the table used was an old chair. In the spring of 1849, MR. DAVIS came to Princeton Township and settled in the northern part, and there remained ten years. In 1870, he purchased the farm on which he now lives. MRS. DAVIS died July 21, 1856, and MR. DAVIS was married January 10, 1857, to MISS JUDA A. FRANKLIN, of Tippecanoe County. To them have been born nine children - WILLIAM M., JAMES K., LUTHER L., ALEXANDER H., GRIFFITH G., ELLA J., EDWARD G., LETTIE E. and HARRY B. MR. and MRS. DAVIS are members of the Methodist Episcopal Church, and he is a Republican and a member of the Masonic Lodge at Wolcott."