This stream is the most northern tributary of the Green River south of the Uinta Mountains. It rises in that range, but at a lower altitude than the branches of the Uinta, and has a southeasterly course 48 miles in length. On its lower course, at an altitude of 5,500 feet, are 75 square miles of arable land of excellent quality, a few acres of which are now cultivated. There is sufficient water in the stream during the critical season to irrigate 25 square miles. HENRYS FORK. But a small portion of the valley of Henrys Fork lies within the Territory of Utah, but this portion includes its best lands. A beautiful natural meadow is here found, affording a large quantity of hay to the ranchmen of that country. The altitude is great, the valley being 6,000 feet above the level of the sea, and hence liable to late and early frosts. About 10 square miles can be redeemed by irrigation. The volume of the stream is sufficient to irrigate a much larger tract, but a part is needed for other lands which lie farther up the river, within the Territory of Wyoming. THE WHITE RIVER. The White River enters the Green from the east, about two miles below the mouth of the Uinta. This stream rises in Colorado, and has only a small portion of its course in Utah, but lying within the boundaries of the Territory are 75 square miles of arable land which may be irrigated with its water. The river was measured in October, 1877, near its mouth, and flowed 734 cubic feet per second. High water usually occurs in June, and the critical period in the irrigation of the land is probably in August, when the stream should flow at least double the volume of October, or, 1,468 cubic feet per second. This would be greatly in excess of the amount needed to irrigate the available land in Utah, and, from the best information attainable, it seems doubtful if it could be used higher up on the course of the stream. THE GREEN RIVER. _Brown’s Park._--Brown’s Park is a valley through which the Green River meanders. Three or four small streams head in the mountains to the north and a like number in the mountains to the south and find their way into the river in the midst of the park. But a small portion of the park lies within Utah and the small streams will be used for irrigation in the portion which falls in Colorado. The flood plain lands of the Green are extensive, and here many natural meadow lands are found, interspersed with fine groves of cottonwood. Some of the bench lands are well adapted to irrigation, but a portion of them and the foot hills back of them are naked, valueless bad-lands. When the general industries of the country shall warrant the great expenditure necessary, the Green will be taken out to irrigate the bench lands on either side. About 10 square miles of these bench lands will fall within Utah.