The council might have been considering also the conducting of the yearly feast of Okeepa, the most important of all Mandan ceremonies. This centered about the legend of the Ark and the First Man, and was regarded as being an essential part of the origin and existence of the tribe. It took place in the summertime, usually lasting about four days. The feast of Okeepa contained many features common to the sun dance of the other Plains tribes, particularly the element of self-torture. Skewers were thrust through the loose flesh of the dancer's chest, thongs attached, and the dancer thereby hauled up toward the roof of the council lodge until his body was six or eight feet off the ground. Often other skewers were thrust through the skin of the back, and weights attached by thongs and allowed to drag over the floor of the lodge as the dancer swung about the pole. Thus suspended, the warrior boasted of his prowess and bravery until he was released by the breaking of the flesh. This torture was thought necessary to secure the blessings of food, shelter, protection from enemies, and long life. While the hunters were away, some of the women, engaged in the immemorial food-getting practice of fishing, went out on the river in the tublike bullboat--so-called because it was made from the skin of a single buffalo bull, stretched over a willow frame. Others went along the bluffs and through the valleys, digging tipsin roots, and gathering berries, cherries, and plums. But probably by far their most important occupation economically was their work in the gardens. As far back as their traditions go, the tribes of the Missouri Valley seem to have been agriculturists. Along the river each family kept a field or garden, variously estimated at from one to four or five acres in size. These fields were held by the family with a sort of perpetual lease from the community, the term of the lease being dependent only on the condition that good use be made of the land. There was apparently no concept of the white man's practice of fertilizing the soil; when an old field grew impoverished, a new one was selected. A fence of forked sticks protected the crops from horses, while here and there on the outskirts of the fields a sentry brave was on duty to guard the women from the ever dreaded Sioux. Aiding the women were a few old men, too feeble for the chase. A variety of tobacco, several varieties of sunflowers, squashes, pumpkins, and beans, and a dozen varieties of corn grew in the gardens. Early travelers say the ears of corn were extraordinarily small.