He answered 'arrived free' on one of the census. I havent been able to trace his actual arrival though. The information provided by ivorex above led me to do a search myself. I found henry's parents as henry and mary rather than henry and elizabeth. the mary seems to have been a mary peasnall which would fit, since she came from a family of brickmakers and that was henry's occupation when he came to australia. im still wondering if there was another henry knight with parents william and elizabeth though, as the date of birth given by ivorex is the same.