[1] Dudley describes two rival attempts to smelt iron with coal instigated by supporters of Parliament during the Civil War and the Interregnum.
Dudley visited both sites and having examined their furnaces and production methods, when asked his opinion, informed the proprietors that they would fail.
The first attempt was by Captain Buck, with the backing of many parliamentary officers including Oliver Cromwell, with technical help from Edward Dagney, an Italian.
Dudley reapplied for a patent from Charles II, in 1660 stating "and seeing no man able to perform the mastery of making of iron with pit-coal or sea-coal, ... [without my] laudable inventions the author was, and is, unwilling [that they] should fall to the ground and die with him".
[2] A significant feature of his great work Metallum Martis is a map showing Dudley Castle where he correctly identifies the order and geographic layout of strata of coal and ironstone under survey.