of the bottom it is placed on the ground and a little loose soil is drawn up to serve as a support and in this it is turned slowly with the hands as required (pl. XVII, c). As the lower coils become dry they are smoothed with a polishing stone with strokes made from below upward; if a part has become too hard to be easily rubbed down the hand is dipped into the vessel of water that is within reach, and applied to the spot.
When the last coil has been shaped a dark red shale is ground in water until the liquid has become quite thick; this is applied to the outer surface with the hands. As the slip dries it is rubbed with the polishing stone until it becomes hard and smooth.
After drying over night the vessel is ready for burning. A very shallow pit is dug and a fire is kept in it for some time to dry the earth thoroughly, then a little dry mesquite or decayed willow wood is spread in the depression, and the vessel is laid on its side upon the wood and entirely covered with sticks laid up "log-cabin fashion." In the specimen shown in figure 52 the wood had burned away in about twenty minutes. The photograph was taken as the burning brands fell from the sides.
The final step, if the vessel is to be decorated, is to apply the black mesquite pigment with a sharpened stick (pl. XVII, d), made from Baccharis glutenosa, which has a large pithy center. The vessel is again subjected to heat for a few minutes until the decoration has assumed a deep black color, when it is finished.
Finished Products
Water reservoirs or coolers (fig. 53, a, b) are the largest and finest pieces of fictile ware made by the Pimas and Papagos. The latter carry on a thriving trade with the whites by supplying each house with one or more of these big round-bottomed pots, which are so porous that the evaporation from the outside measurably cools the water within, Although the term "olla" is applied to all Indian pottery in the Southwest, the word generally refers to this particular class of vessels. One will be found set in a three-forked post under the arbor at every Pima home.[1] An olla was secured which had been hidden away among the rocks in the hills for many years (fig. 54). It is among the smallest of those used for water coolers, and may well serve here to illustrate the minimum size and also a variation in decoration.[2]
Ollas with angular profile are not uncommon (fig. 55).
Cooking pots (pl. XVIII, a) are more numerous than the water
