With an estimated population in 1925 of 2,999,239, Chicago is the second largest city in the United States, and although it is a thousand miles from the ocean, it is one of the greatest ports in our country. The low, flat land on which the city is built was once covered by the waters of Lake Michigan. Chicago has no natural harbor, but by widening and deepening the mouth of the Chicago river and by protecting it by breakwaters an excellent harbor has been made. The River itself, which used to flow into the lake, has been transformed into a drainage canal by which the waters of Lake Michigan flow into the Illinois River and finally into the Mississippi. Chicago is the largest meat market in the world and the greatest railroad center.
