BUTTE, the largest city of Montana, U.S.A., on the west slope of the continental divide, at an elevation of 5,755ft.; the county seat of Silver Bow county. It is on Federal highways Io and 91, and is served by four trans-continental railways: the Chicago, Milwaukee, St. Paul and Pacific, the Great Northern, the Northern Pacific, and the Union Pacific. It has a fine airport covering nearly 6o acres. The area is 5.2sq. miles. The popula tion in 1920 was 41,611, of whom 11,454 were foreign-born white, and was 39,532 in 1930 by the Federal census; in 188o the popula tion was 3,363, and in 1900, 30,470.
Butte is the principal railroad and business centre of the Rocky Mountain north-west, the largest city between Minne apolis and Spokane north of Salt lake. Basically it is a huge mining camp, on "the richest hill in the world." Its surface in the mining district is gridironed with railway tracks to the mines and dotted with shaft-houses, smokestacks, and steel hoist f rames. Underground the rocks are honeycombed with work ings, some to a depth of 3,60o feet. It is also an important trad ing centre, wholesale and retail, has a large tourist traffic, and manufactures a variety of products, valued in 1925 at $4,108,478. Formerly fumes from the smelters killed all vegetation, and the general appearance of the city was desolate indeed by day, though at night it had a fantastic beauty. At present, how ever, most of the ore is treated at Anaconda and Great Falls; trees and grass have reappeared, and some beautiful residential districts and parks have been developed. The assessed valuation of property in 1925 was $19,350,785. The Montana school of mines, established in 1893, is situated here.
Gold was panned from gravel near the present site of Main street in 1864, and before these placer operations were worked out (1867) they had yielded about $1,500,000. Silver ores were first successfully treated in 1875. Production of silver reached its peak in 1887, and practically disappeared as a primary indus try with the drop in the price in 1893. Production of copper on a large scale began in 1882, and by 1900 the output amounted to nearly half the total for the country. To the end of 1924 the Butte district of a few square miles produced 8,622,814,852 lb. of copper, besides 190,993,$27 lb. of lead, 1,876,718,111 lb. of zinc, 1,630,489 oz. of gold, and 399,801,572 oz. of silver, amount ing in value to $1,841,531,619. The city was laid out in 1866, and incorporated in 1879. It grew slowly until the railways reached it in the '8os. The population was 241 in 1870; 3,363 in 188o; 10,723 in 1890; and 30,470 in 1900. There are hot medic inal springs at several points near by. To the west is Big Butte, a sharp conical peak, from which the city takes its name. The Lewis and Clark national monument, 45m. East, includes a cavern boo x 400ft. in size, not yet fully explored, with intricate passages and numerous chambers filled with curious stalagmites and stalactites.