In entire conformity with this, the succession in the methods of the ornamentation of Pueblo pottery seems to have been first by incision or indentation; then by relief; afterward by painting in black on a natural or light surface; finally, by painting in color on a white or colored surface.
As before suggested, the patterns on the coiled, regularly indented pottery (which came to be first known to the world as a type, the "corrugated," through the earlier explorations and reports of Mr. William H. Holmes) were produced simply by emphasized indentation, more rarely by incision, and were almost invariably angular, reproducing exactly the designs on wicker work. Even in comparatively recent examples of the corrugated ware this is true; for, once connected with a type, a style of decoration, both seem to have been ever after inseparable, with at most but slight modification of the latter. One of these modifications, in both method and effect, was in the adoption of the raised or relief style of ornamentation found, with rare exceptions in the Southwest, only on corrugated ware, and on the class which in modern times has replaced it there, vessels used in cookery. Although never universal, this style deserves passing attention as the outgrowth of an effort to attain the effect of contrast produced by dyed or painted splints on wicked work before the use of paint was known in connection with pottery. The same kind of investigation indicates that the Pueblos largely owed their textile industries and designs, as well as their potter's art, to the necessity which gave rise to the making of water-tight basketry. The terms connected with the rudimentary processes of weaving and embroidery, and the principal patterns of both (on, for example, blankets, kirtles, sacred girdles, and women's belts), are mostly susceptible of interpretation, like the terms in pottery, as having a meaning connected with the processes of basket plaiting and painting. This renders the conventional character of Pueblo textile ornaments easy of comprehension, as well, as the very early, if not the earliest, origin of loom-weaving among our Indians in the desert regions of America.
Henceforward, then, we have only to consider decoration by painting. The probability is that this began as soon as the smooth surface in pottery was generally made; evidence of which seemingly exists; as eating bowls are, even to the present day, decorated principally on the interior; not, as may be supposed, because the exterior is more hidden from view, but because, as we have seen on a former page, bowls were made plain inside before the corrugated type formed on basket bottoms had been displaced by the smoothed type; and were naturally first decorated there with paint. It must be constantly borne in mind that a style of decoration once coupled with a kind of ware, or even a portion of a vessel, retained its association permanently.
It must have been early observed that clay of one kind, applied even thinly to the exterior of a vessel of another kind, produced, when burned, a different color. With the discovery that clays of different kinds burned in a variety of colors, to some extent irrespective of the methods and the materials used in firing, there must likewise have been hinted, we may safely conclude, the efficacy of clay washes as paint, and of paint as a decorative agent.
Among the ceramic remains from the oldest pueblo sites of the Southwest, pottery occurs, mostly in four varieties: the corrugated or spiral; the plain, yet rough gray; white decorated with geometric figures in black; and red, either plain or decorated with geometric devices in black and white. The gray or dingy brown, rough variety, resulted when a corrugated or coiled jar had been simply smoothed with the fingers and scraper before it was fired. A step in advance, easily and soon taken, was the additional smoothing of the vessel by slightly wetting and rubbing its outer surface. Even this was productive only of a moderately smooth surface, since, as learned by the Indian potters long before, in their experience with the clay-plastered parching-tray, it was necessary to mix the clay of vessels with a tempering of sand, crushed potsherds, or the like, to prevent it from cracking while drying; this, of course, no amount of rubbing would remove. Hence, by another easy step, clay unmixed with a grit-tempering, made into a thin paste with water, and thickly applied to the half-dried jar with a dab or brash of soft fiber, gave a beautifully smooth surface, especially if polished afterward by rubbing with water-worn pebbles. The vessel thus prepared, when burned, assumed invariably a creamy, pure white, red-brown or, other color, according to the quality or kind of the clay used in making the paste with which it had been smoothed or washed.
Thus was achieved the art of producing at will fictiles of different colors, with which simple suggestion painting also became easy. Black, aside from clay paste, was almost the first pigment discovered; quite likely because the mineral blacks from iron ores, coal, and the various rocks used universally among Indians for staining splints, etc., would be the earliest tried, and then adopted, as they remained unchanged by firing. Thus it came about, as evidenced by the sequence of early remains in the Southwest, that the white and black varieties of pottery were the first made, then the red and black, and later the red with white and black decoration. Take, as an example, the latter. Of course it was a simple mode to employ the red (ocherous) clay for the wash, the blue clay (which burned white) for the white pigment in making lines, and any of the black minerals above mentioned for other marking.
In these earliest kinds of painted pottery the angular decorations of the corrugated ware or of basketry were repeated, or at the farthest only elaborated, although on some specimens the suggestions of the curved ornament already occurred. These resulted, I may not fear to claim, from carelessness or awkwardness in drawing, for instance, the corners of acute angles, which, "cutting across-lot" would, it may be seen, produce the wavy or meandering line from the zigzag, the ellipsoid from the rectangle, and so on.
Precisely in accordance with this theory were the studies of my preceptor, the lamented Prof. Charles Fred. Hartt. In a paper "On Evolution in Ornament," published in several periodicals, among them the Popular Science Monthly of January, 1875, this gifted naturalist illustrated his studies by actual examples found on decorated burial urns from Marajó Island. I must take the liberty of suggesting, however, that upon some antecedent kind of vessel, the eyes of the Amazonian Islanders may have been, to give Professor Hartt's idea, "trained to take physiological and æsthetic delight in regularly recurring lines and dots"; not on the pottery itself, as he seemed to think, for decoration was old in basketry and the textiles when pottery was first made.