The arms are those of Trevor impaling Weldon. The first Baron Trevor of Bromham entered the law under Charles II, becoming Solicitor General, Attorney General, and in 1702 Lord Chief Justice of the Common Pleas, before being created Baron in 1711. He was later Lord Privy Seal and Lord President of the Council and died in 1730. He was married for the second time in 1704, to his cousin Anne Weldon, of St. Lawrence Jewry, London.
See D. S. Howard, The Private Trader, 1994, p.193, no.222, for an identical tankard in the Hodroff Collection.