The men heat the sweat-house, shut it up closely, and sit down. Sweat pours from them like rain. When they have sweated sufficiently, all go to the river and swim. After that the people, men and women, go into the sweat-house. One doctor or two will begin to sing. Young unmarried men or women who are candidates present themselves. The doctors suck out of these all that is bad in them, all that is impure, unclean. They suck the forehead, breast, back, arms. At times they suck out blood; at times something sharp like a fine bone comes out. They suck out everything that is evil. When they have finished sucking, the doctor sings again, and puts a yellowhammer's feather into each ear of the candidate. The feather may go in out of sight, or the doctor puts it on the person's head, and the feather may sink through his skull. Now the people dance, and especially the candidates for the dignity of doctor. The chief goes out, stands on the housetop, and calls to all the yapaitu in the rocks, in the water, in Olelpanti, in the trees, in bathing springs, to come. "We are going to make doctors," says the chief; "you must come and help my people." After this the chief goes in, and they close every hole, every chink in the sweat-house; close them all safely. There is no fire, no light, inside. When they have begun to talk in the sweat-house, one doctor calls to all the spirits of yapaitu in the east, west, north, south to come. Pretty soon a spirit may be heard on the housetop; spirits make a whistling noise when they come. That moment a man or woman falls down, and all know that the spirit has gone into that person's head. Now the doctor calls, "One more; one more!" In a moment another whistling may be heard as the spirit touches the housetop and goes in. Another man or woman falls; the spirit has entered that one. The persons into whom spirits have entered know nothing. They become as if crazy, as if they had lost their wits. They try to go to the housetop. Some try to climb the central pole; some want to leave the sweat-house; they know nothing for half an hour perhaps. One doctor keeps on calling spirits, and they come one at a time. Many doctors may be made in one night, or a few, or none. There are always many people in the sweat-house to whom spirits will not come. The spirits never go into people unless they like them. The spirit looks straight through a man and knows him immediately.