There are different kinds of marrow in bones, as at the ends of bones, or in spongy bone; yet this is on the way toward the perfection of the finest marrow. Hard cartilage covers this spongy substance, and the little pouch of the knee covers that hard cartilage. In this pouch the joint-fluid is elaborated by cooking; relative to the cartilage and marrow, this joint-fluid is a first matter. The physician does not aim to cure the joint-fluid, the little knee-pouch, the hard cartilage, or the spongy bone and its marrow, but the finest marrow. He knows that if his best medicine penetrates to the finest marrow, it also heals the weaker parts to the extent their nature requires. It does not, however, change them into marrow; it changes an evil accompanying quality into a good one. So it is with metals or ores. The medicine or tincture does not aim to cure sulphur, arsenic, or marcasite, but the metal. If cast upon sulphur, arsenic, or marcasite, it does not make them wholly gold and silver, but gives them a purer solar nature. It is like the mother-marrow, changed from its defect or disease to a better and healthier nature and finally, through digestion and maturation, into the finest marrow. In the same way sulphur, arsenic, and marcasite made solar can afterward be made into gold and silver through digestion and maturation, though not, as with metal, into pure gold and silver in the molten state. Let us now descend from corruption or putrefaction to separation, conjunction, and regeneration: first of universal chaotic water, and afterward of all things universally and generally.