weft. While many handsome blankets are
still made only of the colors and material above described, American
yarn has lately become very popular among the Navajos, and many fine
blankets are now made wholly, or in part, of Germantown wool.

The black dye mentioned above is made of the twigs and leaves of the
aromatic sumac (_Rhus aromatica_), a native yellow ocher, and the gum
of the pinon (_Pinus edulis_). The process of preparing it is as
follows: They put into a pot of water some of the leaves of the sumac,
and as many of the branchlets as can be crowded in without much
breaking or crushing, and the water is allowed to boil for five or six
hours until a strong decoction is made. While the water is boiling
they attend to other parts of the process. The ocher is reduced to a
fine powder between two stones and then slowly roasted over the fire
in an earthen or metal vessel until it assumes a light-brown color; it
is then taken from the fire and combined with about an equal quantity
in size of pinon gum; again the mixture is put on the fire and
constantly stirred. At first the gum melts and the whole mass assumes
a mushy consistency; but as the roasting progresses it gradually
becomes drier and darker until it is at last reduced to a fine black
powder. This is removed from the fire, and when it has cooled
somewhat it is thrown into the decoction of sumac, with which it
instantly forms a rich, blue-black fluid. This dye is essentially an
ink, the tannic acid of the sumac combining with the sesquioxide of
iron in the roasted ocher, the whole enriched by the carbon of the
calcined gum.

[Illustration: PL. XXXIV.--NAVAJO WOMAN SPINNING.]

There are, the Indians tell me, three different processes for dyeing
yellow; two of these I have witnessed. The first process is thus
conducted: The flowering tops of _Bigelovia graveolens_ are boiled for
about six hours until a decoction of deep yellow color is produced.
When the dyer thinks the decoction strong enough, she heats over the
fire in a pan or earthen vessel some native almogen (an impure native
alum), until it is reduced to a somewhat pasty consistency; this she
adds gradually to the decoction and then puts the wool in the dye to
boil. From time to time a portion of the wool is taken out and
inspected until (in about half an hour from the time it is first
immersed) it is seen to have assumed the proper color. The work is
then done. The tint produced is nearly that of lemon y