The mouth of the Colorado is in latitude 31 degrees 53 minutes and longitude 115 degrees. The source of the Grand River is in latitude 40 degrees 17' and longitude 105 degrees 43' approximately. The source of the Green River is in latitude 43 degrees 15' and longitude 109 degrees 54' approximately. The Green River is larger than the Grand and is the upper continuation of the Colorado. Including this river, the whole length of 18 CANYONS OF THE COLORADO. powell-canyons-2.jpg PA-RÚ-NU-WEAP CANYON. the stream is about 2,000 miles. The region of country drained by the Colorado and its tributaries is about 800 miles in length and varies from 300 to 500 miles in width, containing about 300,000 square miles, an area larger than all the New England and Middle States with Maryland, Virginia and West Virginia added, or nearly as large as Minnesota, Wisconsin, Iowa, Illinois, and Missouri combined. There are two distinct portions of the basin of the Colorado, a desert portion below and a plateau portion above. The lower third, or desert portion of the basin, is but little above the level of the sea, though here and there ranges of moun- THE VALLEY OF THE COLORADO. 19 tains rise to an altitude of from 2,000 to 6,000 feet. This part of the valley is bounded on the northeast by a line of cliffs, which present a bold, often vertical step, hundreds or thousands of feet to the table-lands above. On the California side a vast desert stretches westward, past the head of the Gulf of California, nearly to the shore of the Pacific. Between the desert and the sea a narrow belt of valley, hill, and mountain of wonderful beauty is found. Over this coastal zone there falls a balm distilled from the great ocean, as gentle showers and refreshing dews bathe the land. When rains come the emerald hills laugh with delight as bourgeoning bloom is spread in the sunlight. When the rains have ceased all the verdure turns to gold. Then slowly the hills are brinded powell-canyons-3.jpg BIRD'S-EYE VIEW OF THE CLIFFS. until the rains come again, when verdure and bloom again peer through the tawny wreck of the last year's greenery. North of the Gulf of California the desert is known as "Coahuila Valley," the most desolate region on the continent. At one time in the geologic history of this country the Gulf of California extended a long distance farther to the northwest, above the point where the Colorado River now enters it; but this stream brought its mud from the mountains and the hills above and poured it into the gulf and gradually erected a vast dam across it, until the waters above were separated from the waters below; then the Colorado cut a channel into the lower gulf. The upper waters, being cut off from the sea, gradually evaporated, and what is known as Coahuila Valley was the bottom of this ancient upper gulf, 20 CANYONS OF THE COLORADO.