Amylum is prepared from every kind of wheat, and from winter-wheat[154] as well; but the best of all is that made from three-month wheat. The invention of it we owe to the island of Chios, and still, at the present day, the most esteemed kind comes from there; it derives its name from its being made without the help of the mill.[155] Next to the amylum made with three-month wheat, is that which is prepared from the lighter kinds of wheat. In making it, the grain is soaked in fresh water, placed in wooden vessels; care being taken to keep it covered with the liquid, which is changed no less than five times in the course of the day. If it can be changed at night as well, it is all the better for it, the object being to let it imbibe the water gradually and equally. When it is quite soft, but before it turns sour, it is passed through linen cloth, or else wicker-work, after which it is poured out upon a tile covered with leaven, and left to harden in the sun. Next to the amylum of Chios, that of Crete is the most esteemed, and next to that the Ægyptian. The tests of its goodness are its being light and smooth: it should be used, too, while it is fresh. Cato,[156] among our writers, has made mention of it. CHAP. 18.—THE NATURE OF BARLEY. Barley-meal, too, is employed for medicinal purposes; and it is a curious fact, that for beasts of burden they make a paste of it, which is first hardened by the action of fire, and then ground. It is then made up into balls, which are introduced with the hand into the paunch, the result of which is, that the vigour and muscular strength of the animal is considerably increased. In some kinds of barley, the ears have two rows of grains,[157] and in others more; in some cases, as many as six.[158] The grain itself, too, presents certain differences, being long and thin, or else short or round, white, black,[159] or, in some instances, of a purple colour. This last kind is employed for making polenta: the white is ill adapted for standing the severity of the weather. Barley is the softest of all the grains: it can only be sown in a dry, loose soil,[160] but fertile withal. The chaff of barley ranks among the very best; indeed, for litter there is none that can be compared with it. Of all grain, barley is the least exposed to accidents, as it is gathered before the time that mildew begins to attack wheat; for which reason it is that the provident agriculturist sows only as much wheat as may be required for food. The saying is, that “barley is sown in a money-bag,” because it so soon returns a profit. The most prolific kind of all is that which is got in at Carthage,[161] in Spain, in the month of April. It is in the same month that it is sown in Celtiberia, and yet it yields two harvests in the same year. All kinds of barley are cut sooner than other grain, and immediately after they are ripe; for the straw is extremely brittle, and the grain is enclosed in a husk of remarkable thinness. It is said,