Though the pottery of the Ácomas is less durable than that of the Zuñis, its designs have much more variety—trees and leaves, birds and flowers, being introduced along with geometrical patterns. There are specific reds and grays used in the Ácoma and Zuñi pottery; and a bright green pigment applied in circular blotches before firing, that gives something approaching a glaze afterwards, is found at both Ácoma and Laguna. Among those pueblos where pottery and earthenware utensils form a conspicuous feature of their civilization, Mr. James Stevenson[263] mentions Ácoma and the great similarity of its pottery to that of Laguna, though the Laguna potters use more colors. He calls some of the designs at Ácoma “very spirited.” Many of the jars in the Santa Fé museum have combinations of Ácoma and Sía designs—the bird of each pueblo being quite distinct. We may briefly summarize here the value of our knowledge concerning ceramics to the other forms of cultural development of any people and find it applicable to the inter-relationships of those American Indians who practised the art. Since it can never be known when the modelling of clay was first practised, there is fascination in the suggestion that it came in some long-past day when a man walking on clay softened by rain noticed his own footprints. The rudest savage may well have discovered with what ease he could fashion a crude but useful vessel from moist earth, but the first baking of such a utensil probably occurred through some happy accident. We know that sun-dried bricks were used in early building, but no clay cups thus treated would have served to hold liquids. The student searching for some standard by which to measure the creative attainment of a semi-civilized race has chosen as most universal the work of the early potters, and the interesting fact is disclosed that the first attempts in ceramics of all peoples are curiously alike in processes, in modes of decoration, and in adaptation to practical needs. There is in the decorative addition of painting to pottery something much more valuable than mere ornament, namely, a conventionalized representation, graphically expressed, of the mythology and the social habits of a race, so that even without written records it becomes possible for us to form a fairly clear idea of its cultural development. In short, the study of pottery has disclosed so much of race origins that it is now regarded as essential to an understanding of the history and mythology, and, in many countries, of the industries no less than of the arts, of ancient peoples.