He was commissioned as a Lieutenant in one of the volunteer battalions in the Royal Sussex Regiment in 1885.

[6] He was awarded his Kent county cap in 1886, a year after his brother Richard Thornton.

[8][9] Thornton was described in his Wisden obituary as a "good and free hitter and a useful lob bowler", batting right-handed and bowling underarm.

[4][8] He toured North America with EJ Sanders XI in 1885 as part of a team captained by his brother Richard, playing in both of the first-class matches on the tour against the Gentlemen of Philadelphia, and played in Portugal for a team led by Tom Westray in 1895.

He married his first wide, Ernestine Alice Hawker, in 1877 at Honiton in Devon, the county where his parents had owned property at Knowle near Sidmouth.