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:
“There is a patent office at the seat of government of the universe, whose managers are as much interested in the dispersion of seeds as anybody at Washington can be, and their operations are infinitely more extensive and regular.”
—Henry David Thoreau (1817–1862)
“She smiled and that transfigured me
And left me but a lout,
Maundering here, and maundering there,
Emptier of thought
Than the heavenly circuit of its stars
When the moon sails out.”
—William Butler Yeats (1865–1939)