Looking northward from the church, a wall of broken stones, similar to the one we already noticed at the south, meets the eye. The _mesilla_ itself terminates east and west in rocky ledges of inconsiderable height, and the wall stretches across its entire width of 39 m.--129 ft. Its distance from the church is 10 m.--33 ft.; and it thus forms, with the northern church wall, a trapezium of 10 m.--33 ft. This enclosure is said to have been the church-yard.[96] Beyond it the mesilla and its ruined structures appear in full view; and from the church to the northern end, which is also its highest point, it has exactly the form of an elongated pear or parsnip. Hence the name given to it by Spanish authors of the eighteenth century, "el Navon de los Pecos."[97] This fruit-like shape is not limited to the outline: it also extends to the profile. Starting from the church, there is a curved neck, convex to the east, and retreating in a semicircle from the stream on the west. At the end of this neck, about 200 m.--660 ft.--north of the church, there is a slight depression, terminating in a dry stream-bed emptying into the bottom of the Arroyo de Pecos south-westward; and beyond this depression the rocks bulge up to an oblong mound, nearly 280 m.--920 ft.--long from north to south, and at its greatest width 160 m.--520 ft.--from east to west. At the northern termination of this mound the _mesilla_ curves to the north-east, and finally terminates in a long ledge of tumbled rocks, high and abrupt, which gradually merges into the ridges of sandy soil towards the little town of Pecos.[98] Pl. I., Fig. 5, gives a tolerably fair view of the _mesilla_. Pl. I., Fig. 1, is designed to exhibit its appearance as seen from below, the highest elevation above the stream being nearly 30 m.--95 ft. The rock of the _mesilla_ is a compact, brownish-gray limestone. It is crystalline, but yet fossiliferous, very hard, and not deteriorating much on exposure. Its strata dip perceptibly to the south-west; consequently the western rim is comparatively less jagged and rocky than the eastern, and the slope towards the stream more gentle, except at the north-western corner, where the rocks appear broken and tumbled down over the slopes in huge masses.