<a href="https://en.wikipedia.org/wiki/L._Frank_Baum" class="extiw" title="en:L. Frank Baum">L. Frank Baum</a> (1856–1919) served for two years as a cadet at the Peekskill Military School, which overlooked the Hudson. He was about 12 years old in this 1868 photograph.
Photographer not credited
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