Although I normally research military history, I found the following interesting.

This bollard will be found by the River Thames on the north side of Vauxhall Bridge in Millbank which was close to the notorious Millbank Prison (1816-1890). From 1788 to 1868 this bollard was near the steps where convicts boarded transport ships to Australia after being found guilty of mainly petty crimes which included Stealing furnishing from a lodging, stealing an item worth over one shilling (a week’s pay for a worker); buying and selling stolen goods, but one of the strangest crimes which could lead to deportation was impersonating an Egyptian!
From 1788 to 1868 around 162,000 consisting of mainly petty criminals were transported to Australia.
Alan Malcher