My grandfather drove a truck for Texaco in the early 1900's with a two horse team. A few years later he drove trucks for Texaco when they discontinued using horses for delieveries. He referred to his occupation as a "teamster". iIn the 1930's he did become a member of the Teamsters. He drove for Texaco for over 30 years until he died a from appendicitis in 1939 at age 57. I have posted pictures of both trucks on Scott William's. "History's Time Portals to Old St. Louis" http://www.usgennet.org/usa/mo/county/stlouis/yeckel-bussiness.htm Joan Schaller Yeckel