Spring Valley (7,035) is a coal-mining center and the largest city in Bureau County. Depue (1,339) has recently estab lished a zinc smelter, and is therefore growing in population.
Along the Middle Illinois are found Hennepin (451), Henry (1,667), Lacon (1,495), Chillicothe (1,851), Peoria Heights (683), Averyville (2,668), Peoria (66,950), East Peoria (1,493), Bartonville (1,636), and Pekin (9,897). Five of for an electric railroad. Ottawa (9,536) is the county seat of La Salle County. Plate-glass and clay products are among its manufactures. Utica (1,250) has one of the few natural cement factories in the United States.
La Salle (11,537), Peru (7,984), and Oglesby (3,194) in the western part of La Salle County are known as the "tri-cities." La Salle and Peru are on the north side of the river at the ter minus of the Illinois and Michigan Canal. Oglesby is on the south side of the Illinois in the valley of the Ver milion River. Oglesby is the name of the post office and railroad sta tion, although the city is incorporated under the name of Portland. Portland cement is the chief manufactured product. Zinc-smelting is the important indus try of La Salle and Peru. A large Portland cement factory is in operation in La Salle. Several coal mines are operated in the vicinity of the tri-cities. The cities and villages of the Illinois Valley in La Salle County contain 42 per cent of the population of the county. If to these we add Streator and Mendota we find 62 per cent of the population of the county living in cities.
Spring Valley (7,035) is a coal-mining center and the largest city in Bureau County. Depue (1,339) has recently estab lished a zinc smelter, and is therefore growing in population.
Along the Middle Illinois are found Hennepin (451), Henry (1,657), Lacon (1,495), Chillicothe (1,851, Peoria Heights (583), Averyville (2,668), Peoria (66,950), East Peoria (1,493), Bartonville (1,536), and Pekin (9,897). Five of cothe, Peoria Heights, Averyville, Peoria, and Bartonville are in Peoria County, and their combined population consti tutes 73 per cent of the population of the county. Peoria Heights, Averyville, Peoria, and Bartonville form a single urban area on the west side of the river, and Peoria street-car service extends to East Peoria on the east side of the river. These five cities form a single industrial community and their combined population comprises 48 per cent of the total popula tion of 29 cities and villages, each with a population of more than 450, along the 27S miles of the Illinois River. Pekin is on
the east side of the river ten miles below Peoria. The transport service between Pekin and Peoria brings Pekin within the Peoria indus trial district. With this added population, 54 per cent of the inhab itants of the cities and villages of the Illinois Valley are to be found in the Peoria district, extending along the course of the river for a distance of about 15 miles.
Peoria has been, from the earliest settlement of the Illinois Valley, the most important city in it. Natural conditions provided at Peoria favorable opportunity for crossing a wide river. Farm Creek, entering the river opposite Peoria, with its swift current in flood times, carried great loads of sedi ment from the hills of the Bloomington terminal moraine into the sluggish waters of the Illinois River. This sediment accu mulated in the form of an alluvial fan on the east side of the river. The building of this fan made the river narrow at this point, and by partially damming the river, Lake Peoria was formed as a widened portion of the river, extending upstream to Chillicothe, a distance of 20 miles. Below Peoria the river is everywhere wider and more difficult to cross than at Peoria.
Opposite the Farm Creek fan is an extensive river terrace, easy of access from the river front, and well above serious flood dangers. Upon this terrace Peoria was established. As the city grew the terrace was fully occupied. Now it extends up the "West Bluffs" and spreads out on the extensive upland beyond. In pioneer days a river ferry at Peoria marked a very important break in transportation. A ferry is more easily established and more readily maintained where the stream is narrow. No other point along the Illinois River for a distance of more than 200 miles offered a crossing as favorable as the one at Peoria. Wagon bridges and railroad bridges could span the river more readily at Peoria than elsewhere below the Great Bend. The coming of the railroad, therefore, increased Peoria's importance, and it became the chief railroad center of the interior of the state, surpassed only by Chicago on the lake and East St. Louis, the front door of St. Louis, on the Mississippi. Peoria is the home of Bradley Institute, one of the important schools of the state for technical training.