Author Thomas Ryan, a member of the Gettysburg Foundation and the Civil War Trust, has written other books and articles on the Civil War. In this illustrated study for history buffs and scholars, he describes the intelligence resources of the Signal Corps and the Bureau of Military Information during the Civil War, and looks at how intelligence gathered from spies, civilians, and newspapers influenced the military decisions of the Army of the Potomac and the Army of Northern Virginia. The book offers day-to-day analysis of the impact of intelligence on strategy and military tactics during events from early June to mid-July 1863. Black and white historical photos and maps are included, along with contemporary photos of locations. Annotation ©2015 Ringgold, Inc., Portland, OR (protoview.com)