Postal History of John Butterfield's Overland Mail Co. on the Southern & Central Routes including Butterfield's Pony Express 1858-1864 - Paperbackby Bob O. Crossman (Author) This new full color book reports on the mail carried by Butterfield's Overland Mail between September 1858 and March 1861 on the Southern Ox Bow Route, and beginning in July of 1861 on the Central Route. Also, to include additional information and artifacts from US transcontinental mail carried immediately before and immediately after the existence of Butterfield's Overland Mail Co. In most instances within his previous