They believe that there are two main sources of disease: one of these is in the mind of the patient himself, which desires something, and will vex the body of the sick man until it possesses the thing required. For they think that there are in every man certain inborn desires, often unknown to themselves, upon which the happiness of individuals depends. For the purpose of ascertaining desires and innate appetites of this character, they summon soothsayers, who, as they think, have a divinely-imparted power to look into the inmost recesses of the mind. These men declare that whatever first occurs to them, or something from which they suspect some gain can be derived, is desired by the sick person. Thereupon the parents, friends, and relatives of the patient do not hesitate to procure and lavish upon him whatever it may be, however expensive, a return of which is never thereafter to be sought. The patient enjoys the gift, divides a portion of it among the soothsayers, and often on the next day departs from life. Commonly, however, the sick recover, plainly because their illnesses are slight; for, in the case of more severe complaints, these soothsayers are more cautious, and deny the possibility of ascertaining what the patient desires; then they bewail him whom they have given up, and cause the relatives to put him out of the way. Thus they kill those afflicted with protracted illness, or exhausted by old age, and consider this the greatest kindness, because death puts an end to the sufferings of the sick. They display the same benevolence towards children deprived of their parents, whom they prefer to see dead rather than to see them miserable. They believe that another source of disease is the hidden arts and the charms of sorcerers, which they seek to avert by means of absurd ceremonies. Often they expel noxious humors by sweating. They inclose a certain portion of the hut with pieces of bark and cover it with hides, in order that no air may enter. Within they pile stones heated to a high temperature. They enter naked and toss their arms while singing. But, strange to say, they will leave this heat, dripping with perspiration, and in the very coldest part of winter cast themselves into a lake or river, careless of pleurisy.