sists of a mile-deep gorge cut through a hundred miles of high forested plateau, and is principally remarkable for its brilliant and variegated color effects and the extraordinary sculpturing of its interior by ages of erosive action. The lateral canyons contain many cliff dwellings. While the main canyon is more than 10 miles wide at all points, the river itself runs through an inner chasm of solid granite and contains many rapids which have claimed a number of lives and have not been often successfully navigated. A cable ferry crosses the river at one point.

That part of the Grand Canyon National Monument south of the river, which is the part most often visited, is administered by the United States Forest Service as part of the Tusayan National Forest. The forest supervisor's headquarters is at Williams, Ariz., and the local forest ranger is stationed at Rowe Well, 3 miles southwest of the railroad terminal. To preserve the scenic value of points along the rim, especially thorough protection is provided against forest fires.

The easiest way to reach the Grand Canyon is by way of the Santa Fe Railway, which maintains a branch line extending from its main transcontinental line at Williams, Ariz., to the south rim of the canyon itself. At this point first-class hotel facilities and livery service are afforded, while excellent roads and trails lead into the canyon and to points along the rim in either direction.

Transcontinental motorists are also visiting the canyon in increasing numbers. Good branch roads lead to the canyon from the main ocean-to-ocean highway.

Under the protection given by the Forest Service, under the authority of the proclamation establishing the Grand Canyon National Game Preserve, game animals have steadily increased. The preserve is now estimated to contain 10,000 head of blacktail deer and a large number of bighorn or mountain sheep. Mountain lions and other predatory animals are systematically destroyed by forest officers. Steps were taken to create a national park of the Grand Canyon of the Arizona, and a bill (H. R. 6331) providing for such purpose was introduced in Congress April 20, 1911. The bill, however, did not become a law. The Association of American Geographers has recommended that the above-mentioned park be designated as Powell National Park, and the Geological Society of America has approved the naming of the national park in the Grand Canyon of the Colorado after its explorer, Maj. John Wesley Powell.

The sundry civil act approved March 4, 1909, appropriated $5,000 for the purpose of procuring and erecting on the brink of the Grand Canyon in the Grand Canyon Forest Reserve (within the limits of the Grand Canyon National Monument) a memorial to Maj. John Wesley Powell in recognition of his distinguished public service as a soldier, explorer, and administrator of Government scientific work, and provided that the design for the memorial and the site should be approved by the Secretary of the Interior. Thereafter the Secretary designated as an advisory committee Dr. W. H. Holmes, Chief of the Bureau of Ethnology, Dr. C. D. Walcott, Secretary of the Smithsonian Institution, and Col. H. C. Rizer, chief clerk of the United States Geological Survey, to assist in determining the character of the monument and the selection of the site. This committee

submitted designs prepared by Mr. J. R. Marshall, of Washington, D. C., and his plans were referred to the Commission of Fine Arts and have received its approval.

Subsequently, in 1915, at the instance of the Secretary of the Interior, these plans were revised in certain respects by Mr. Mark

Grand Canyon National Monument, within Grand Canyon National Forest, Ariz.; created January 11, 1908.

Daniels, general superintendent and landscape engineer of national parks, and Mr. Walter Ward, engineer of the Reclamation Service, was placed in charge of actual construction work on the memorial. This work was commenced late in the summer of 1915, and was completed on October 26, 1915.

JEWEL CAVE NATIONAL MONUMENT.

Jewel Cave National Monument was created by proclamation dated February 7, 1908.

Jewel Cave, which is located 13 miles west and south of Custer, the county seat of Custer County, S. Dak., was discovered on August 18, 1900, by two prospectors, Albert and F. W. Michaud, whose attention was attracted by the noise of wind coming from a small hole in the

Jewel Cave National Monument, within Black Hills National Forest, S. Dak., Tps. 3 and 4 S., R. 2 E., Black Hills meridian; created February 7, 1908.

limsetone cliffs on the east side of Hell Canyon. In the hope of discovering some valuable mineral and the source of the wind, these men, in company with one Charles Bush, enlarged the opening.

The cave, as far as known, is located in limestone formation and is apparently the result of action of water. A prominent geologist who visited this cave believes it to be an extinct geyser channel. The main passage has been explored a distance of over 3 miles, although it has been opened up for visitors only 1 miles, a short distance beyond Milk River, which is a stream flowing through a white limestone, which gives the water the appearance of milk.

The limits of the main passage and side galleries are as yet unknown. Explorations have been carried in a northerly direction and vertically 100 feet below the entrance.

On either side of the main passage are side galleries and chambers of various sizes. The first chamber, or gallery, is lithographic limestone and resembles the Gothic style of architecture. About 500 feet from the entrance, the walls and roofs of a number of the chambers are lined with a thick crystalline calcite and the floor is of calcite and manganese.

Within the different chambers one may see different colored chert. It varies in color, some having a peculiar light-green tint, also dark green and bronze. The surface of the rock is smooth and should take a high polish.

The chambers are connected with narrow passages generally, although wide passages are sometimes found. The narrow passages are very picturesque. The "box work" or honeycomb crystallization is very attractive. The color ranges from a light brown to a deep chocolate shade, and the boxlike cavities, covered with minute crystals, stand in relief from the ground mass.

Geodes of various size and shape are found in the walls and passageways, galleries, and chambers. The brilliancy of some of these cavities is very beautiful.

The explorers have been careful observers of the action of the wind within the cave. They have discovered that ordinarily the wind blows in and out of the cave for regular periods, the periods of blowing in and out being 15 hours each, although they have known the periods to be of 72 hours' duration. Other wind passages have been discovered in the vicinity of the cave.

The cave is a wonderful creation of nature and worthy of many hours of study. As yet the cave has not been robbed of its beautiful specimens. A good automobile road leads to the cave from Custer, about 12 miles distant. Good spring water is plentiful near the cave.

WHEELER NATIONAL MONUMENT.

Wheeler National Monument was created by proclamation of December 7, 1908, and is located on the east slope of the divide between the head of the West Fork of Bellows Creek on the south side of the range and the head of the South Fork of Saguache Creek on the north side of the range and about 1 mile southeast of Half Moon Pass, in sections 17 and 20, township 42 north, range 2 east, New Mexico principal meridian, Mineral County, Rio Grande National Forest, Colo.

The tract lies on the southern slope of the ridge which forms the crest of the Continental Divide. It is traversed from north to south by numerous deep canyons with very precipitous sides, the intervening ridges being capped by pinnacle-like rocks, making it practically impossible to cross the tract from east to west, even on foot. There are also many crevices cutting the ridges transversely, making an intricate network of ravines separated by broken, precipitous ledges and broken mesas.

It is probable that the formation found here is the result of a succession of outpourings of lava and showers of volcanic ash which have left a series of nearly horizontal strata of varying degrees of

hardness. Numerous pebbles and breccia of a flint-like rock are embedded in the softer lavas which were probably gathered up by the flowing lava mud from the original bedrock. The formation is for the most part scoriaceous tufa and trachyte, with some rhyolite. The effect of erosion on this formation has been to cut it into sharply defined forms of many kinds. The harder broken rocks embedded in the lavas have acted as veritable chisels, greatly accelerating erosive action and making the lines and angles more sharply defined than

Wheeler National Monument, within Cochetopa and Rio Grande National Forests, Colo., T. 42 N., R. 2 E., New Mexico meridian; created December 7, 1908.

would be the case in ordinary weathering. This erosion is still going on at a remarkably rapid rate, making the place very interesting from the geological point of view.

The fantastic forms resulting from the rapid erosion make this spot one of exceptional beauty. The numerous winding canyons, broken ridges, pinnacles, and buttes form striking and varied scenes. From the most reliable data it is believed that the ill-fated expedition of John C. Fremont, in 1848, reached this immediate vicinity, when disaster came upon the party, compelling it to turn back. Skeletons of mules, bits of harness, and camp equipage are found here, lending force to the recorded data.