A red tugboat moving through the water.
The steam tug HERCULES, built in 1907, navigating on San Francisco Bay.

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HERCULES Statistics
Length 151 feet
Beam 26 feet
Draft 18 feet aft, 10 feet forward
Gross Tonnage 409
Engine 3 cylinder, triple expansion
Cylinders 17", 24", and 41" with 30" stroke. 500 Indicated Horsepower (ihp)
Fuel Type Oil Fuel
Boiler Scotch marine fire tube. 16' diameter, 11' 9" long. Four oil-burning furnaces
  • Hercules is a steam powered tug built for ocean towing
  • The 151-foot ship, of riveted steel construction, still contains her original triple expansion steam engine
  • Built on the East Coast in 1907, she towed her sister ship from Camden, New Jersey around South America to San Francisco
  • Hercules also towed sailing ships, disabled vessels, barges, log rafts, a cassion (a steel structure used for closing the entrance to locks) for a dry dock at Pearl Harbor, and a caisson to help build a Panama Canal lock
  • The tug usually carried a crew of three firemen, three oilmen, a chief and two assistant engineers, three deckhands, cook, two mates and a captain
Xplore Timelooper App - Hercules Steam Tug
Xplore Timelooper App - Hercules Steam Tug

Xplore Timelooper

Xplore Hercules Steam Tug

Come explore the Post-Victorian wonderland of steel and steam aboard this 1907 tugboat with the free Xplore Timelooper App.


Last updated: March 9, 2023

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2 Marina Boulevard,
Building E, 2nd Floor

San Francisco, CA 94123


415 561-7000
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