The drawings were outlined by pecking with a piece of quartz or other silicious rock, to the depth of from a mere visible depression to a third of an inch. Having thus satisfactorily depicted the several ideas, colors were applied which upon examination appear to have penetrated the slight interstices between the crystalline particles of the rock, which had been bruised and slightly fractured by hammering with a piece of stone. It appears probable, too, that the hammering was repeated after application of the colors to insure better results. Upon a small bowlder, under the natural archway formed by the breaking of the large rock, small depressions were found which had been used as mortars for grinding and mixing the colors. These depressions average 2 inches in diameter and about 1 inch in depth. Traces of color still remain, mixed with a thin layer of a shining substance resembling a coating of varnish, though of a flinty hardness. This coating is so thin that it cannot be removed with a steel instrument, and appears to have become part of the rock itself. From the animals depicted upon the ceiling it seems that both beaver and deer were found in the country, and as the beaver tail and the hoofs of deer and antelope are boiled to procure glue, it is probable that the tribe which made these pictographs was as far advanced in respect to the making of glue and preparing of paints as other tribes throughout the United States. Examination shows that the dull red color is red ocher, found in various places in the valley, while the yellow was an ocherous clay, also found there. The white color was probably obtained there, and is evidently earthy, though of what nature can only be surmised, not sufficient being obtainable from the rock picture to make satisfactory analysis with the blow pipe. The composition of the black is not known, unless it was made by mixing clay and powdered charcoal from the embers. The latter is a preparation common at this day among other tribes. An immense granite bowlder, about 20 feet in thickness and 30 in length, is so broken that a lower quarter is removed, leaving a large square passageway through its entire diameter almost northwest and southeast. Upon the western wall of this passageway is a collection of the colored sketches of which Figure 155 is a reduced copy. The entire face of the rock upon which the pictograph occurs measures about 12 or 15 feet in width and 8 in height. The ceiling also contains many characters of birds, quadrupeds, etc. No. 1 in the figure measures 6 feet in height, from the end of the toes to the top of the head, the others being in proportion as represented. The attempt at reproducing gestures is admirably portrayed, and the following explanations are based upon such natural gestures as are almost universally in use: