Tim, I presume that you've seen the "two-page spread" in the back (Plate CLXXIV) of the Atlas to accompany the Official Records (available in reduced facsimile reprint). In Chisolm's "Manual of Military Surgery," 3rd ed., 1864 (available as facsimile 68 from Morningside Press), Plate 1 (in back) has an illus and description of CS army litter and of four-wheel CS ambulance, making ref also to two-wheeled ambulance, which is not illustrated. Chapter Three is devoted to discussion of "the latest" in Europe (Prussian, French) and relates to CS experience. Dr. Chisolm was top-notch medical authority, drawing on early war CS experience (and is the hero in Dr. Frank Slaughter's novel, "In a Dark Garden). I've seen scattered refs to CS ambulance corps, distinctive arm/hat markings, hospital flags, etc., but have never inquired further.
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