Used, divided back, color post card titled "SCENE WASHINGTON PARK, CHICAGO, ILL." posted by CHI. & MIL. AVE. / MAY 25. 1908 / TR. 8 / R.P.O. street car route duplex hand cancel with "R.P.O." in barred oval killer (see scans). Towle CH-6-e variety cancel was used for a 3.97 mile route of the "West Chicago Street Ry." from1902 to 1908  Cancel is somewhat poor strike missing several letters in the town abbreviations and just a faint hint of "R.P.O." in killer. Card made expressly for the S. H. Knox & Co., has creased/damaged corners. Check out other postal history items and post cards listed in my eBay Store. Multiple lots combined, single p&h applied as long as paid per single invoice. Oklahoma residents subject to sales tax. [02/06/21]