At the outbreak of the American Civil War, 160 years ago, the publisher Johnson and Browning (the successor to the J.H. Colton and Company publishing company) published A.J. Johnson’s New Illustrated Family Atlas, with Descriptions. It would later be reprinted several times, and in at least one edition it was printed with stubs bound in so that later changes, such as the addition of new U.S. states in the union, could be glued in to keep the atlas updated.
The eighth plate in the atlas was this time clock, showing the difference of time between Washington, D.C., and 133 different places around the world. Thus, for example, the user of this chart would know that if it is noon in Washington it would be twelve minutes after noon in New York.
Just a couple of years before this diagram was printed, the Italian mathematician Quirico Filopanti proposed a global time zone system. And just a couple of years after this diagram was printed, Charles F. Dowd proposed a system of time zones for railroads. He published a proposal for four U.S. time zones in 1870, with the first of the four time zones centered on Washington, DC. Thus, this diagram was addressing an issue of enormous importance as railroad drew the corners of the world closer and closer.