[Illustration: Fig. 52. Pi-gummi ovens of Mashongnavi.] [Illustration: Fig. 53. Cross sections of pi-gummi ovens of Mashongnavi.] In its perfected form the cooking pit in Tusayan takes the place of the more elaborate oven used in Zuñi. Figs. 52 and 53 show two specimens of pits used for the preparation of pi-gummi, a kind of baked mush. These occur on the east side of Mashongnavi. They project 6 or 8 inches above the ground, and have a depth of from 18 to 24 inches. The débris scattered about the pits indicates the manner in which they are covered with slabs of stone and sealed with mud when in use. In all the oven, devices of the pueblos the interior is first thoroughly heated by a long continued fire within, the structure. When the temperature is sufficiently high the ashes and dirt are cleaned out, the articles to be cooked inserted, and the orifices sealed. The food is often left in these heated receptacles for 12 hours or more, and on removal it is generally found to be very nicely cooked. Each of the pi-gummi ovens illustrated above is provided with a tube-like orifice 3 or 4 inches in diameter, descending obliquely from the ground level into the cavity. Through this opening the fire is arranged and kept in order, and in this respect it seems to be the counterpart of the smaller hole of the Zuñi dome-shaped ovens. When the principal opening, by which the vessel containing the pi-gummi or other articles is introduced, has been covered with a slab of stone and sealed with mud, the effect is similar to that of the dome-shaped oven when the ground-opening or doorway is hermetically closed. No example of the dome-shaped oven of pre-Columbian origin has been found among the pueblo ruins, although its prototype probably existed in ancient times, possibly in the form of a kiln for baking a fine quality of pottery formerly manufactured. However, the cooking pit alone, developed to the point of the pi-gummi oven of Tusayan, may have been the stem upon which the foreign idea was engrafted. Instances of the complete adoption by these conservative people of a wholly foreign idea or feature of construction are not likely to be found, as improvements are almost universally confined to the mere modification of existing devices. In the few instances in which more radical changes are attempted the resulting forms bear evidence of the fact. [Illustration: Fig. 54. Diagram showing foundation stones of a Zuñi oven.] [Illustration: Plate LXXX. Old adobe church of Zuñi.]