'A Relation Concerning the Making of Allum By Mr Daniel Colwall' 'Allum is made of a Stone digged out of a Mine, of a Sea-Weede, and of Urine; The Mine of stone is found in most of the Hills betweene Scarborough and the River of Tees in the County of Yorke, and also neare Preston in Lancashire' That 'snake stones' were found with the stones that make alum Read to the Royal Society 11 August 1661 27 September 1661