On Architecture

10. The alder, which is produced close by river banks, and which seems to be altogether useless as building material, has really excellent qualities. It is composed of a very large proportion of air and fire, not much of the earthy, and only a little moisture. Hence, in swampy places, alder piles driven close together beneath the foundations of buildings take in the water which their own consistence lacks and remain imperishable forever, supporting structures of enormous weight and keeping them from decay. Thus a material which cannot last even a little while above ground, endures for a long time when covered with moisture.

11. One can see this at its best in Ravenna; for there all the buildings, both public and private, have piles of this sort beneath their foundations. The elm and the ash contain a very great amount of moisture, a minimum of air and fire, and a moderate mixture of the earthy in their composition. When put in shape for use in buildings they are tough and, having no stiffness on account of the weight of moisture in them, soon bend. But when they become dry with age, or are allowed to lose their sap and die standing in the open, they get harder, and from their toughness supply a strong material for dowels to be used in joints and other articulations.

12. The hornbeam, which has a very small amount of fire and of the earthy in its composition, but a very great proportion of air and moisture, is not a wood that breaks easily, and is very convenient to handle. Hence, the Greeks call it “zygia,” because they make of it yokes for their draught-animals, and their word for yoke is zuga/. Cypress and pine are also just as admirable; for although they contain an abundance of moisture mixed with

13. The cedar and the juniper tree have the same uses and good qualities, but, while the cypress and pine yield resin, from the cedar is produced an oil called cedar-oil. Books as well as other things smeared with this are not hurt by worms or decay. The foliage of this tree is like that of the cypress but the grain of the wood is straight. The statue of Diana in the temple at Ephesus is made of it, and so are the coffered ceilings both there and in all other famous fanes, because that wood is everlasting. The tree grows chiefly in Crete, Africa, and in some districts of Syria.

14. The larch, known only to the people of the towns on the banks of the river Po and the shores of the Adriatic, is not only preserved from decay and the worm by the great bitterness of its sap, but also it cannot be kindled with fire nor ignite of itself, unless like stone in a limekiln it is burned with other wood. And even then it does not take fire nor produce burning coals, but after a long time it slowly consumes away. This is because there is a very small proportion of the elements of fire and air in its composition, which is a dense and solid mass of moisture and the earthy, so that it has no open pores through which fire can find its way; but it repels the force of fire and does not let itself be harmed by it quickly. Further, its weight will not let it float in water, so that when transported it is loaded on shipboard or on rafts made of fir.