Lead.

Lead cannot be better preserved than in cold earth and a moist place, corresponding to its own nature. Nothing preserves a magnet better than filings of iron or steel. No magnet’s strength weakens if placed in them; rather, its virtue increases daily.

The preservation of the magnet: iron filings.

The preservation of salts.

As to the preservation of salts and everything of a salty nature which can be included under the name salt—of which there are more than a hundred kinds—know that they must be kept in a warm dry place, in wooden containers, well protected from air. They must not be stored in glass, stone or metal, for in these they dissolve and become water and amalgam, which cannot happen in wood.

The preservation of liquors and oils.

The preservation of certain waters and liquors pressed from plants, roots and all other fruits and growing things must also be understood. They readily acquire mould and mildew, as though a skin formed over them. Store such waters or liquors in a glass narrow above and broad below, filling it to the top; then add a few drops of olive oil so that the entire water or liquor is covered. The oil floats above and preserves the liquor or water from mould and mildew for a long time. No water or liquor covered with oil can ever become mouldy or foul-smelling. In this way two waters, two liquors or two wines can also be kept separately in one glass without mixing—not only two but three, four, five or more, provided oil is interposed. They are separated by oil as by a wall which does not allow them to join and unite. Oil and water are two contraries, and neither can mix with the other. As oil prevents waters from uniting, so conversely water prevents oils from mixing.

How clothing is to be preserved.

For preserving cloth and garments so that moths do not gnaw or inhabit them, nothing is better than mastic, camphor, ambergris and musk. Best of all is civet: it not only preserves them from moths but also drives away moths together with other worms, fleas, lice and bedbugs.

How wood is to be preserved.

All wood, whether in buildings, bridges, ships or anywhere else, can also be preserved so that it never rots: in or under water, out of water, in or under earth, out of earth, exposed to rain, wind, air, snow or ice, in summer or winter. It can also be protected from worm-eating and the generation of any worms, whenever it was cut. This preservative is a great arcanum against every putrefaction, so outstanding a secret that none can compare with it. It is nothing but oil of sulphur, whose process is as follows. Powder common yellow sulphur and place it in a cucurbit; pour on enough of the strongest aqua fortis to stand four transverse fingerbreadths above it. Draw it off by distillation three or four times, finally to dryness. Place the black and reddish sulphur remaining at the bottom on marble or in glass, and it will readily dissolve into an oil. This is a great secret for preserving wood so that it never rots and remains protected from worms. Sulphur prepared and converted to oil in this way stains wood anointed with it so that it cannot be washed out. Many other things can also be kept from putrefaction in this oil of sulphur, especially cords and ropes on ships and masts, on wagons, fishing nets, snares of birdcatchers and hunters, and similar things often used in water and rain which otherwise readily decay and break, as well as linen and many comparable things.

Fixed oil of sulphur.