Patent Sails
Patent sails were invented by William Cubitt in 1813. They combine the shutters of the spring sail with automatic adjustment of the roller reefing sail. Their construction is similar to that of the spring sail. Adjustment of patent sails can be made without stopping the mill.
- Air brakes
In 1860, the English millwright Catchpole fitted an automatic air brake to the ends of patent sails. These were longitudinal shutters at the tip of each sail, which opened up if the wind got too strong, thus slowing the sail.
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Famous quotes containing the words patent and/or sails:
“The cigar-box which the European calls a “lift” needs but to be compared with our elevators to be appreciated. The lift stops to reflect between floors. That is all right in a hearse, but not in elevators. The American elevator acts like the man’s patent purge—it works”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
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