These conditions are well-described by Sophus Müller, who says,[19] “A great part of the work on flint must be designated as luxury, and was done with the sole intent of producing a masterpiece of handiwork. When making an adze blade all that is needed for practical purposes is a good cutting edge. Smoothness of face, back and sides is not necessary, particularly since a large portion of these were covered by the attachment to the handle. With coarse and conchoidal chipping the blade would be equally serviceable. However, the maker wanted to produce excellent stone work, to the making of which he devoted all the care, taste and skill at his command and by this the manufactured objects undoubtedly increased in value. These objects might be called therefore, in the strict sense of the term, works of artistic industry.” [19] Sophus Müller, Nordische Altertumskunde, Strassburg 1897, Vol. I, p. 190. All these examples show that complete automatic control of a technique, and regularity of form and surface pattern are intimately correlated. [Illustration: Fig. 6. Part of surface of wooden sail, Vancouver Island.] [Illustration: Fig. 7. Painted board, Tierra del Fuego.] [Illustration: Fig. 8. Bushman designs from ostrich eggs and from horn bracelet.] [Illustration: Fig. 9. Kaffer headrests.] However, besides these, attempts at decoration occur in which a mastery of technique has not been attained. Among a few tribes almost all artistic work is of this character. Among the inhabitants of Tierra del Fuego are found only meagre examples of painting, lacking in skill (fig. 7). The patterns are simply dots and coarse lines in which the arrangement is the essential artistic element. It is intelligible that a feeling for symmetry may exist without the ability of perfect execution. The modern Bushmen scratch patterns on ostrich eggs which serve as receptacles for water (fig. 8). Here we find the intent to give expression to form but with inadequate means. It is important to note that the same motive, two circles connected by a narrow band, occurs several times in these etchings. The circle might be suggested to the workman by the perforation of the shell of the ostrich egg through which the water is poured out, but the combination can hardly be derived on the basis of Bushman industries. Shall we consider the pattern as the result of the play of their imagination or as an attempt at representation? It seems to me important to note that the neighbors of the Bushmen, the negroes of the Zambezi, use the same pattern and that rows of triangles and diamonds, such as are used by the Bushmen, are found on their implements also (fig. 9). The pattern may therefore have come from an outside source.[20] Perhaps the decoration on ostrich eggs is poor only on account of the difficulties of handling the material. At least the zig-zag patterns (fig. 8), found on a bracelet, show a much greater technical perfection than those found on the ostrich eggs.