Free thoughts on quacks and their medicines, [electronic resource] : occasioned by the death of Dr. Goldsmith and Mr. Scawen; or, a candid and ingenuous inquiry into the merits and dangers imputed to advertised remedies: ---In which, an investigation of the nature and origin of their composition has been attempted: and the degree of confidence they deserve, ascertained. ---Wherein, also, have been occasionally interspersed some few animadversions tending to defend Minerals in general, and exculpate Mercury and Antimony in particular, from the ill-judged and ill-grounded aspersions thrown against them; by proving the superiority of the productions of the Mineral, over those of the Vegetable, Kingdoms. Dedicated to the Legislature in general, or, both Houses of Parliament.