Alexander Gardner's "Photographic Incidents of the War, #277" (Library of Congress)
A plate version, a more successful exposure from the same camera position, appears in Gardner's Sketchbook.
It is titled "A Sharpshooter's Last Sleep," and is accompanied by a Gardner's imaginative narrative caption.
If you have red/cyan 3D glasses, click on the stereocard above to see its anaglyph.
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