NAVAJO DYE STUFFS. 615 
a native yellow ocher, Specimen No, 7, Catalogue No. 153354, and the gum 
of the pinon (Pinus edulis), Specimen No. 8, Catalogue No. 153355, 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 éan 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 as- 
sumes 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 prog- 
resses it gradually becomes dryer 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 eal- 
cined gum. 
The effect and color of the dyes are shown in the accompanying 
specimens on wool of the Navajo sheep. 
No. 1. Cat. No. 153348. Blue—dyed with indigo. 
No. 2. Cat. No. 153349. Yellow—a decoction of the flowering tips of 
Bigelovia graveolens, mixed with almogen (a native impure alum). 
No. 3. Cat. No. 153350. Dull red—dyed with bark of Alder, Almus 
incana, var Viresceno (Watson), and bark of Cercocarpus parvifolius, a 
kind of mountain mahogany; the mordant, fine ashes of the juniper. 
No. 4. Cat. No. 153351. Orange—dyed with roots of a sorrel— 
Rumex hymeuosepolum. 
No. 5. Cat. No. 153352. Wool—half natural white and half dyed 
black, carded together. 
No. 6. Cat. No. 153353. Black dye—made of a decoction of the twigs 
and leaves of aromatic sumac, Rhus aromatica, yellow ocher and gum 
of pinon, Pinus edulis. 
No. 7. Cat. No. 153354. Native ocher—for making the black dye. 
No. 8. Cat. No. 153355. Powder of yellow ocher and pinon gum, 
caleined together—for making black dye. 
