He was born in the West End of London to bedstead manufacturer James Tonkin and Jemima Stephens, and migrated to Melbourne in 1854.
He was a goldminer at Ballarat, Bendigo, Mount Alexander and Ararat, and from 1856 to 1859 pursued business in Geelong.
He followed the gold rush to New Zealand, but returned to Victoria in 1866, moving to New South Wales in 1868.
During his time in New Zealand he married Mary Ann Smith, with whom he had twelve children.
[2] In 1887 he was elected to the New South Wales Legislative Assembly as one of two Free Trade members for East Macquarie.