And Metaphysic calls for aid on Sense.

See Mystery to Mathematics fly;

In vain! they gaze, turn giddy, rave, and die.

Pope—“The Dunciad” (641–648).

Elements and Phlogiston.

The ancient idea that earth, air, fire, and water were the elements of Nature was held by chemists in the 18th century. Empedocles appears to have been the author of this theory, which was adopted by Aristotle. Some speculative philosophers, however, taught that all of these were derived from one original first principle; some held that this was water, some earth, some fire, and others air. Paracelsus, who does not seem to have objected to this idea, contributed another fantastic one to accompany it. According to him everything was composed of sulphur, salt, and mercury; but he did not mean by these the material sulphur, salt, and mercury as we know them, but some sort of refined essence of these. These three essentials came to be tabulated thus:—

Salt.Sulphur.Mercury.
Unpleasant and bitter.Sweet.Acid.
Body.Soul.Spirit.
Matter.Form.Idea.
Patient.Agent.Informant or movent.
Art.Nature.Intelligence.
Sense.Judgment.Intellect.
Material.Spiritual.Glorious.

This is taken from Beguin, who explains that the mercury, sulphur, and salt of this classification are not those “mixt and concrete bodies such as are vulgarly sold by merchants. Mercury, which combines the elements of air and water, Sulphur represents Fire, and Salt, Earth.” “But the said principles, to speak properly, are neither bodies; because they are plainly spiritual, by reason of the influx of celestial seeds, with which they are impregnated: nor spirits, because corporeal, but they participate of either nature; and have been insignized by Phylosophers with various names, or at the least unto them they have alluded these.”

Instances of the combination of these principles are given. If you burn green woods, you first have a wateriness, mercury; then there goes forth an oleaginous substance easily inflammable, sulphur; lastly, a dry and terrestrial substance remains, salt. Milk contains a sulphurous buttery substance; mercurial, whey; saline, cheese. Eggs: white, mercury, yolk, sulphur, shell, salt. Antimony regulus, mercury, red sulphur conceiving flame; a salt which is vomitive.