Mississippi Squadron during American Civil War. Mostly <i>tinclad</i> gunboats, with one <i>City</i>-class ironclad (probably one of <i>timberclads</i> visible in a background behind her)
Unknown author<span style="display: none;">Unknown author</span>
<i><a rel="nofollow" class="external text" href="https://archive.org/stream/photographichist06mill#page/n12/mode/1up">The Photographic History of The Civil War in Ten Volumes: Volume Six, The Navies</a></i>. The Review of Reviews Co., New York. 1911, p.35