"When Tar-waters of different Degrees of Strength were put into Florence Flasks, with other inverted Flasks fixed on them, and all were placed in the same Vessel of hot Water; on breaking the upper Flasks, the volatile acid Spirit could very sensibly be tasted, especially that of the stronger Tar-water; which shows that these Waters are impregnated therewith: and which when distilled from Turpentine, Dr. Boerhaave in his Chemistry says, is the best vegetable Acid that is known."