many people (covicted for what would now be considered [petty] offences),  were sent to trial, imprisoned and later trasported to van dieman's land on the calcutta
calcutta was a [ship] which transported convicts to van dieman's land in the 1850s
"many people (covicted for what would now be considered [petty] offences),  were sent to trial, imprisoned and later trasported to van dieman's land on the calcutta" What is the definition of "calcutta"?