produced by a coating of opaque whitewash. Upon this white surface the
figures are afterwards drawn.

The only colors used in decorating pottery are black, red, and some
shade of brown. But of this we will speak more fully when we come to
describe the peculiar methods practiced by the different tribes in
making and adorning pottery.

Although there is a strong general similarity in this colored
ornamentation, the great variety of details renders it difficult to
classify the figures so as to convey a correct idea of them to the
reader. We shall therefore have to refer him to the numerous cuts and
the colored plates which have been introduced for the purpose of
illustrating the catalogue.

The following general statement is about all that can be said in
reference to them before descending to specific details.

So far as the coloring is concerned they are of two kinds, those having
the figures wholly black, and those which are partly black and partly
brown or red. The differences in the decorated pottery appear to be
always accompanied by certain other variations sufficient to warrant
speaking of them as different varieties or groups. The former (those
having the figures wholly black), which are made of the ordinary plastic
blue clay, have only the upper half or two-thirds of the body of the
vessel overlaid with the white coating for receiving the decorations,
the lower part being uncoated, and of the natural pale red or salmon
color produced by burning, but usually well polished. As additional
distinguishing features of this group we notice that the shape is more
generally globular, the workmanship rather superior, and the pottery