I found this classic late steam era photograph from the former Milwaukee Road at my Link page Yesteryear Depot.Com, which is located to the right of your computer screen at www.yesteryeardepot.com
Railfan photographer Fred C. Stoes, captured this streamlined 1930's era Alco 4-6-4 Hudson type steam locomotive on the head end end, of one of the Milwaukee Road's famous Hiawatha streamlined passenger trains. This train is photographed just north of Chicago Union Station, near the Canal Street curve. The train is building up steam, and will soon depart from Chicago Illinois.
During this period of time in the late 1940's, the Milwaukee Road was rapidly dieselizing their locomotive fleet, and steam locomotives were being phased out. Although these 4-6-4 passenger type locomotives were known as "Hudson" types on most railroads during the steam era, the Milwaukee Road had refered to these as "Baltics". Many of these engines were phased out during the early to mid 1950's, and had spent their final years of operation minus the streamlined shrouding, hauling Chicago area commuter trains. Sadly none of these have been preserved, as the Milwaukee Road only saved a few steam locomotives for historic preservation.