In 1875 Irish American John P. Holland sent the U.S. Navy this design for an experimental 15 1/2-foot long torpedo boat. Designed to operate underwater, the submarine required 1/10 horse power and could be managed by one man. Although this design was rejected, Holland continued to improve his invention and on October 12, 1900, the U.S. Navy commissioned the first true submarine, the 64-foot USS Holland.
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