Almost a miracle how Joe could have got himself bancrupt, owing as much as 20,000 pounds http://archive.spectator.co.uk/article/3...eld-on-saturday

That is, besides gunmaking, he got quite a bit of land with his wife, which was used for an urban development project, i.e. building and letting houses. http://www.british-history.ac.uk/report.aspx?compid=50006#n154

Manton's contracts for East India Company are regularily mentioned, but I can't find any details yet.