"Neither human nor animal bodies can be multiplied or propagated without decomposition; the grain and all vegetable seed, when cast into the ground, must decay before it can spring up again; moreover, putrefaction imparts life to many worms and other animalculæ.... If bread is placed in honey, and suffered to decay, ants are generated ... maggots are also developed by the decay of nuts, apples, and pears. The same thing may be observed in regard to vegetable life. Nettles and other weeds spring up where no such seed has ever been sown. This occurs only by putrefaction. The reason is that the soil in such places is so disposed, and, as it were, impregnated, that it produces these fruits; which is a result of the properties of sidereal influences; consequently the seed is spiritually produced in the earth, and putrefies in the earth, and by the operation of the elements generates corporeal matter according to the species of nature. Thus the stars and the elements may generate new spiritual, and ultimately, new vegetable seed, by means of putrefaction.... Know that, in like manner, no metallic seed can develop, or multiply, unless the said seed, by itself alone, and without the introduction of any foreign substance, be reduced to a perfect putrefaction." [Illustration: FIG. III.] The action of the mineral agent in perfecting substances is often likened by the alchemists to the conjoining of the male and the female, followed by the production of offspring. They insist on the need of a union of two things, in order to produce something more perfect than either. The agent, they say, must work upon something; alone it is nothing. The methods whereby the agent is itself perfected, and the processes wherein the agent effects the perfecting of the less perfect things, were divided into stages by the alchemists. They generally spoke of these stages as _Gates_, and enumerated ten or sometimes twelve of them. As examples of the alchemical description of these gates, I give some extracts from _A Brief Guide to the Celestial Ruby_. The first gate is _Calcination_, which is "the drying up of the humours"; by this process the substance "is concocted into a black powder which is yet unctuous, and retains its radical humour." When gold passes through this gate, "We observe in it two natures, the fixed and the volatile, which we liken to two serpents." The fixed nature is likened to a serpent without wings; the volatile, to a serpent with wings: calcination unites these two into one. The second gate, _Dissolution_, is likened to death and burial; but the true Essence will appear glorious and beautiful when this gate is passed. The worker is told not to be discouraged by this apparent death. _The mercury of the sages_ is spoken of by this author as the queen, and gold as the king. The king dies for love of the queen, but he is revived by his spouse, who is made fruitful by him and brings forth "a most royal son."