The tendency of this period is then to place a greater dependence on magic than on food, drink, and grave furniture. It is, therefore, not surprising to find introduced, for the first time, the use of magical texts in the burial chamber,--the so-called Pyramid Texts. In the burial chamber in the pyramid of Unas, last king of the Fifth Dynasty, and in the pyramids of the kings of the Sixth Dynasty, the walls are covered with long magical texts or chapters--the oldest form of the so-called book of the dead or "book of the going forth by day." The texts were probably somewhat older, but are now used for the first time in this manner, no doubt owing to the increased facility in carving stone. In these the various powers of the other world are invoked by the incidents of the Osiris-Isis legend, to preserve the dead body, to feed the _ka_, and to assist the other spirit, the _ba_, in its struggles with supernatural powers. The pyramid texts introduce us to three important ideas,--(1) a curious plurality of the spirit existence, (2) a condition of immortality better than that of the old underworld or Earu, and (3) most important of all, the identification of the king with Osiris according to the terms of the Osiris-Isis legend. In all the older offering formulas it is only the _ka_ spirit which is mentioned. Here is the body perishable and destructible; here is the life, the _ka_ which fills every limb and vessel of the body and must, therefore, have the same form. When death comes, the _ka_ spirit, the image of the man, remains near the body, and this spirit it was which was the object of the rites and offerings in the funerary chapel. But besides this _ka_, it appears for the first time that the king at any rate possesses also a soul called a _ba_. In later times we see that every man possessed a _ba_, and we learn that each god possessed several _ba's_. But it is in the pyramid texts that we learn for the first time of the _ba_ of a man, and that man is a king. When death comes, the _ba_ takes flight in the form of a bird or whatever form it wills. All seems confused. The _ka_ was near the body, the _ka_ was in the field of Earu, under the earth ploughing and sowing; the _ba_ is fluttering on the branches of the tree on earth, the _ba_ has fled like a falcon to the heavens, and has been set as a star among the stars. The dead king lives with the gods and is fed by them. The goddesses give him the breast. He lives in the Island of Food. He lives in Earu, the Underworld, a land like Egypt, with fields and canals and flood and harvest. He shares with the gods in the offerings made in the great temples on earth.