White Earth River, the last, is about 100 miles in length and at the mouth a little more than 100 yards wide, contains but little water, always fordable, and not navigable by anything, empties into the Missouri near the commencement of the Great Bend. None of these rivers being navigable except the Missouri, goods are only landed at the following points along that river, viz: Fort Pierre (Sioux), mouth of the Teton River; Fort Clarke (Arikara) at their village; Fort Berthold (Gros Ventres village); Fort Union (Assiniboin), mouth of Yellowstone. Steamboats have gone up the Missouri as high as the mouth of Milk River, but heretofore goods for Fort Benton (Blackfeet), near the mouth of Maria River, have been transported by keel boats from Fort Union. We know of no large navigable lakes in this district, though along the northern boundary there are many small ones, or rather large ponds of water, without any river running through them or visible outlet, being fed by snows, rain, and springs, and diminished by evaporation and saturation. Lakes of this kind are to be met with in many places on the plains and differ in size from 100 yards to 2 or 3 miles or even more in circumference, are not wooded, and contain tolerably good water. Small springs are also common, most of them having a mineral taste, though none are large enough to afford water power. SURFACE OF THE COUNTRY.—The whole country occupied by the Assiniboin is one great plain, hills and timber only occurring where rivers run, in the valleys of which good land for cultivation is found, but the general feature appears to be sterile as regards arable land, producing, however, grasses of different kinds, some of which are very nutritious, and particularly adapted to raising horses, cattle, and sheep. The prairies may be said to be interminable and destitute of the least particle of timber except along the banks of the few streams before mentioned, and even these but thinly wooded. Water, however, can always be found in the small lakes and rivers spoken of. The Assiniboin do not cultivate the soil in any way, though the Gros Ventres and Arikara raise corn and pumpkins to some extent on the Missouri bottoms. By experiments made at or near Fort Union, we find that oats, potatoes, corn, and all garden vegetables grow well if the season be favorable. The soil, being light and sandy, requires frequent rains to produce good crops, which happens about one year in three; the others fail from drought and destruction by grasshoppers, bugs, and other insects. The natural productions of the country are few and such as no one but an Indian could relish. A wild turnip called by them teep-see-na, and by the French pomme blanche, when boiled is eatable, is found in quantity everywhere on the plains, will sustain life alone for a great length of time either cooked or in its raw state, can be dried and preserved for years, or pulverized and made into passable bread.