Hi phill55
It helps hugely if you can give the census reference for anything you have already found

Is this the right one for 1861? RG9/192/109/25
1871 - RG10/385/24/42
17 12 St Helena Place, Clerkenwell
modifiedThomas Leech Head Mar 63 Glazier diamond setter Gloucestersh Bristol
Hannah Leech Wife Mar 61 Middlesex City of London
Mary A Leech Dau Unm 22 Book sewer Middlesex Clerkenwell
Charles Leech Son Unm 17 Jeweller Middlesex Clerkenwell
Alfred Knott Boarder Unm 22 (should be 27) Glass frame maker Middlesex Hackney
Linda