Rock Island, a N. W. county of Illinois, separated from Iowa on the N. W. by the Mississippi river, and intersected by Rock river; area, about 350 sq. m.; pop. in 1870, 29,783. The surface is rolling and the soil very fertile. Coal and limestone occur in large quantities. Several railroads centre at the city of Rock Island. The chief productions in 1870 were 245,820 bushels of wheat, 1,459,653 of Indian corn, 276,575 of oats, 36,980 of barley, 192,531 of potatoes, 17,239 lbs. of wool, 563,122 of butter, and 31,299 tons of hay. There were 7,985 horses, 7,471 milch cows, 12,877 other cattle, 5,667 sheep, and 26,625 swine; 7 manufactories of agricultural implements, 10 of brick, 15 of carriages and wagons, 16 of clothing, 12 of cooperage, 3 of iron castings, 7 of lime, 1 of paper, 18 of saddlery and harness, 2 of sash, doors, and blinds, 2 of woollens, 2 tanning and currying establishments, 2 distilleries, 4 breweries, 10 flour mills, and 10 saw mills. Capital, Rock Island.
Rock Island, a city and the capital of Rock Island co., Illinois, on the Mississippi river, at the foot of the upper rapids, opposite Davenport, Iowa, 3 m. above the mouth of Rock river, and 160 m. W. by S. of Chicago; pop. in 1850, 1,711; in 1860, 5,130; in 1870, 7,890; in 1875, estimated by local authorities at 12,000. It is opposite the W. extremity of Rock island, from which it derives its name. This island, the property of the United States, is 3 m. long, covering 960 acres, is well timbered, and has graded avenues and handsome drives. During and previous to the Black Hawk war it was the site of Fort Armstrong, a series of block houses, and during the civil war an extensive prison for the detention of confederate prisoners of war was situated upon it. Here is the Rock Island arsenal and armory, intended to be the central United States armory. The design embraces ten immense stone workshops, with a storehouse in the rear of each, besides officers' quarters, magazines, offices, etc. Four of the workshops are already completed (1875). The shops will be supplied with motive power from the Moline water power, three fourths of which is owned by the government. The main channel of the Mississippi is N. of the island.
Across the S. channel, from the upper end of the island to Moline, Ill., a dam has been constructed by the United States government, affording extensive water power. The Moline water power is 2 m. E. of the city of Rock Island; the Milan water power in Rock river, 3 m. S. of it. Rock Island is the headquarters of the Rockford, Rock Island, and St. Louis railroad, the S. W. terminus of the Western Union railroad, the W. terminus of the Peoria and Rock Island railroad, and a station on the Chicago, Rock Island, and Pacific, and the Chicago and Southwestern railroads, which here cross the Mississippi on the railroad and wagon bridge built by the government in connection with the arsenal. The railroads and river afford excellent facilities for shipment, and the abundant water power gives ample opportunity for manufactures. The principal establishments are a plough and cultivator factory, a stove foundery, a window-glass establishment, a cotton factory, three lumber mills, and three breweries. There are three national banks, a private bank, four large public school buildings, four denominational schools, two newspapers with daily and weekly editions, and 13 churches, viz.: African Christian, Baptist, Christian, Episcopal, German Lutheran, Methodist, Presbyterian (2), Roman Catholic (2), Swedish Baptist, Swedish Lutheran, and United Presbyterian. Augustana college, a Swedish Lutheran institution, is situated here.