On the issue of slaves in England here is an extract from (Ipswich Journal. 8 February 1752)

Run away from Joshua Steel of Hall Place, Berkshire, a handsome black slave-5ft 4 inches high-the property of Mrs Sarah Steel of Barbadoes, his plantation name is "Sambo" but he has assumed the name of William Gardener, anyone who harbours him will be prosecuted under the law or anyone giving information shall receive one guinea reward.

This was found on:

www.foxearth.org.uk/blog/2005/04/am-i-not-man-and-brother.html

I cannot find any information on the Steels of Barbados. Hall Place has an interesting history as later owners the Easts seem to have been linked to the Easts of Jamaica one of whom based in England and India received a very large amount of compensation. I have already been in email touhc with Berkshire CRO and with Nick Draper. I have now asked a member of the BASA network who is doing some work in the Berkshire CRO to look at Hall Place and its owners/occupiers, and check whether a Berkshire paper for 1752 has survived which may give more information on William Gardener.

Sean