Smart was born in Forest Hill near Marlborough in Wiltshire, into a cricketing family.
He began as an attacking batsman and occasional off break bowler, but became the team's wicket-keeper after the retirement of Tiger Smith in 1930, catching 317 victims while standing behind the stumps and stumping 105 (in addition to 77 catches as an outfielder).
He made 79 dismissals in 1932, a then county record which was bettered by Geoff Humpage in 1985.
He umpired 4 Test matches, all played in England, two involving India in 1946 and two South Africa in 1947.
He also umpired the high-scoring but drawn 1st and 5th Tests against South Africa in 1947, at Trent Bridge and the Oval.