knocking


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knocking

A loud knocking or banging noise made inside a reciprocating engine cylinder during the combustion stroke caused by shock waves produced by the detonating engine. Knocking is an explosion rather than a smooth burning process. It is caused by burning either the wrong fuel or the incorrect amount of fuel. The fuel-air mixture, in this case, ahead of the flame front gets so hot that it explodes and produces a rattling noise, or knocking.
References in classic literature ?
She was evidently not heard by those without, for the knocking recommenced whilst she was speaking, and she recoiled as if she had received a blow on the mouth.
It distressed Annette to such an extent that now, if she went upstairs and heard Sellers' voice in the studio, she came down again without knocking.
I had only to keep knocking on the floor long enough--'
And, mind ye, there's nae knocking at the door possible, when I've got the tray in baith my hands, and mairs the pity, the gout in baith my feet.
Don't leave us in the dark,' said Kags, taking down a candle from the chimney-piece, and lighting it, with such a trembling hand that the knocking was twice repeated before he had finished.
Then, came a loud knocking at the door, and then a hoarse murmur from such a multitude of angry voices as would have made the boldest quail.
Daniel Quilp of Tower Hill, and Sampson Brass of Bevis Marks in the city of London, Gentleman, one of her Majesty's attornies of the Courts of the King's Bench and Common Pleas at Westminster and a solicitor of the High Court of Chancery, slumbered on, unconscious and unsuspicious of any mischance, until a knocking on the street door, often repeated and gradually mounting up from a modest single rap to a perfect battery of knocks, fired in long discharges with a very short interval between, caused the said Daniel Quilp to struggle into a horizontal position, and to stare at the ceiling with a drowsy indifference, betokening that he heard the noise and rather wondered at the same, and couldn't be at the trouble of bestowing any further thought upon the subject.
As the knocking, however, instead of accommodating itself to his lazy state, increased in vigour and became more importunate, as if in earnest remonstrance against his falling asleep again, now that he had once opened his eyes, Daniel Quilp began by degrees to comprehend the possibility of there being somebody at the door; and thus he gradually came to recollect that it was Friday morning, and he had ordered Mrs Quilp to be in waiting upon him at an early hour.
Now, just as Mr Quilp laid his hand upon the lock, and saw with great astonishment that the fastenings were undone, the knocking came again with the most irritating violence, and the daylight which had been shining through the key-hole was intercepted on the outside by a human eye.
An unknown man pushed past her, knocking her to the ground.
Arkansas, (7) however, the Supreme Court made clear that the knock and announce constitutional requirement is not absolute but, rather, that "countervailing law enforcement interests" could make knocking and announcing unnecessary.
In the 3 1/2 years we've been together, he's had 10 wins, no losses, eight knockouts and he is knocking on the door of the heavyweight championship,'' Rappaport said.