The discovery of an extinct volcano explains a great deal of the wonders of the great cañon. The volcano is examined by thousands of tourists, this being one of the spots to reach which scientists are willing to incur countless hardships and risks. No one can tell when the volcano was active, but from the nature of the crater it is perfectly clear that at one time it belched forth volumes of lava, which had a marked effect on the formation of the rock and the lay of the land of the surrounding country. Past the volcano, for many miles, the bright colors already referred to are supplanted by more sombre hues. Occasionally there is a little scarlet, and, as a rule, the sandstone is covered with the mysterious substance brought out of the bowels of the earth by the now silent, but once magnificently awful, mountains. The exploring party to which we have referred, went through 600 miles of cañons, and found that no two miles were really alike. Finally, after three months of hardship, they emerged into an open country, and became almost frantic with joy. Never did country seem so beautiful, or verdure so attractive, and the panorama of beauty which was presented to their view caused them to shout with delight, and to offer up cries of thankfulness for their ultimate deliverance from a series of hardships and dangers which at one time seemed almost insurmountable. The region also abounds with archaeological curiosities and remarkable hieroglyphics. Many of these are found in close proximity to the Grand Cañon of the Colorado, and on the cliffs in which the far-famed cliff dwellers of old took up their abode. Hieroglyphics, marked upon rocks or other lasting substances, have been used by nearly all ancient races to perpetuate the history of certain events among them. Especially true is this of the ancient people who lived in Arizona. The remarkable picture rocks and boulders, with strange symbols upon them, left by the prehistoric races of Arizona, have been the cause of much discussion among those who have seen them, as to who these ancient hieroglyphic makers were. These rock records may be divided into three different kinds, which it is thought were made by two different races. The first, or very ancient race, left records on rocks, in some instances of symbols only, and in other instances of pictures and symbols combined. The later race, which came after the first race had vanished, made only crude representations of animals, birds or reptiles, not using symbols or combinations of lines.