snifting valve

Such and such a time, such and such a day, then trouble with the valve.
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The flawed valve was rapidly replaced by a more robust system.
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This safety valve allows citizens to sound the alarm and challenge those whose views are hateful and totalitarian.
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[W] thout an exchange-rate safety valve you need an alternate way to rebalance economies.
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He also might have a heart-valve problem, but recovery from repair of these generally takes longer than a few days.
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A feed-pump forced water into the boilers; each had a safety-valve with a lever and weight.
Life of Richard Trevithick, Volume II (of 2)|Francis Trevithick
The valve-seat H has formed on its lower surface two crescent shaped long and narrow slits.
The Recent Revolution in Organ Building|George Laing Miller
The discharge-valve was then opened for a moment, allowing a blast of steam to escape, reducing the pressure say to one-half.
Life of Richard Trevithick, Volume II (of 2)|Francis Trevithick
The valve open while the plunger-pole ascended 20 inches, then went the remainder of the 10-feet stroke expansive.
Life of Richard Trevithick, Volume II (of 2)|Francis Trevithick
The engine boy having fixed the safety-valve while he fished for eels, caused an explosion of the boiler.
Life of Richard Trevithick, Volume II (of 2)|Francis Trevithick