1620" INDIANS OF THE SOUTHWEST. 
The patterns are brought out by causing the warp 
instead of the woof to appear in the desired places. 
The colors employed are the natural white and 
brown of the well-washed wool, a gray which results 
from the mingling of these, and various native and com- 
mercial dyes. Black they produced by combining a 
concoction of sumach (Rhus aromatica), roasted ochre, 
and pimon gum. Dull red was obtained by placing the 
Navajo Chief Blanket. 
yarn in a liquid made by boiling the bark of alder and 
mountain mahogany in water. Lemon yellow was 
secured by the use of the yellow flowers of the shrubby 
Bigelovia graveolens and a native alum. Old gold re- 
sulted from rubbing into the wool a paste made of sorrel 
roots and crude alum ground together. In rather early 
days indigo blue was obtained from the Mexicans and 
displaced an earlier native blue. A bright scarlet and a 
