Comparative accuracy in four civil war maps of the Shenandoah Valley: A GIS analysis

摘要

This study compares the accuracy of four maps available to Union and Confederate officers during the 1862 Shenandoah Valley campaign of the American Civil War. It examines historical maps of the Valley of Virginia by the following cartographers: James W. Abert, Hermann Boye and Lewis von Buchholtz, Jedediah Hotchkiss, and Franz Kappner. Both simple and three-tiered sinuosity measures are derived for reference points along study map representations of the Shenandoah river system. These data are then statistically compared to corresponding sinuosity data from USGS topographic quadrangles to identify the relative accuracies of the historical maps. This article offers evidence to refute the common historical assumption that Hotchkiss provided Maj. Gen. Thomas "Stonewall" Jackson with terrain intelligence that was far superior to that available to his Union opponents. Evidence indicates that maps by Union cartographers as well as the prewar Boye-Buchholtz map were at least as accurate, or superior to, the work of Hotchkiss.