NATURAL RESOURCES OF THE COUNTRY. 95 
establishment of the road, may differ very widely from the truth, and it is not unwise to take into 
consideration this inferior but extensive layer of coal, the working of which may at some time 
become desirable and profitable. 
A coarse but generally weak and useless sandstone extends throughout the Missouri and Milk 
rivers. In some places a firm sandstone, suitable for building, is to be found. Sandstone of this 
character was noticed near Fort Union, near the last crossing of Milk river, and it is to be obtained 
in abundance at the “Trois Buttes,” on the eastern base. Several other stones compose these 
mountains, the most valuable of which is a beautiful marble, at times having an alabaster white- 
ness and clearness. 
Lime is to be obtained from near Fort Benton, from the “Trois Buttes,” and from the Rocky 
mountains. i 
Sand, though in a clean state not abundant, is to be found in the beds of the rivers, and 
occasionally at other places in limited quantities. 
Good materials for brick are furnished on the Missouri and Milk rivers. 
Throughout the dry summer and fall season most of the small tributaries making into Missouri 
and Milk rivers are dried up, and both in the intervale and on the prairie there is a scarcity of 
water. The high plateau making back from these rivers affords, however, the opportunity of 
securing the necessary supplies by reservoirs ; and protected from evaporation, there is no reason 
to doubt that water for the uses of a railroad can be supplied as conveniently here as on the 
States’ roads. 
For much valuable information in reference to the country east of the mountains, I will refer 
you to Mr. Lander’s report of the crossings of the Mississippi, D No. 11; Lieutenant Grover’s 
report of the Dead Colt Hillock line, D No. 10; Lieutenant Donelson’s report of the country 
between the White Earth and Big Muddy rivers, E No. 14; Mr. Tinkham’s report of his recon- 
naissance of the Three Buttes and the country between the Milk and Marias rivers, D No. 12; 
and Doctor Evans’s report of his route south of the Missouri, and between the Milk and Missouri 
rivers, D No. 13. Iam particularly indebted to the perseverance and skill of Messrs. Lander 
and Tinkham for much of the valuable statistical information given in this chapter. 
