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Invension of separation prosess
Another important was a invension of separation prosess. A seed of grass is covered by hard skin, and which encroach upon a part of starch, and there are many cases that it was hard to eat as it is. We roast it and powder it, and is eaten without dividing the seed coat. But it was not to eat for living mainly. If we divide skin and remove it, and by collecting only parts of starch, we can get completely new material to eat deliciously. And storage nature is good for dry powder, and variety to eat can be get.
Two metho of separation was used for a kind of a seed. For example for rice or millet, which skin does not encroach upon starch, skin separates it by hull it , after stamp by a stone mill with a dent. The skin can divide by wind. Here are a basic difference between Europe of wheat civilization and the Orient and the Far East civilization of rice. Wheat is easy to grind the grains by rub than pound. If dampness the skin of the grain, the skin is hard to powdered, then can separate by wind. We collect only seeds from the ear which had a seed of grass, and separation method is possible in wind or blows to your mouth to remove an unnecessary part. Because there was a textile of a certain kind for cloth in those days, screen of vine of tree or the fur which make many hole were used to removal of trash. With regret , there is a extremely little possibility that is discovered as remains, because it is easy to decay.
The wall painting in Egypt, which show a system of powder process