Fons salutis, or, The fountain of health opened : in the wonderful efficacy and almost incredible virtue of true oyl, which is made of sulphur vive, set on fire and called commonly, oyl of sulphur per campanam / faithfully collected out of the writings of the most excelling philosopher and unparalel'd physitian of this last age, John Baptist Van Helmont, lately deceased, and confirmed by the experience of Thomas Moulson