 The cupola (reverberatory furnace) long remained in use for smelted copper and lead, and was applied by Robert Lyddall to tin.It is not clear where he obtained his knowledge of metallurgy, but it is possible that Dud Dudley was his teacher; certainly, his lead smelting efforts seem to be foreshadowed by an enterprise involving Dud Dudley at Okham Slade (location unknown) in Clifton, Bristol.Sir Clement died in debt in 1693.