at one blast

For when Men ſhall obſerve the Nature of the Gun-Powder Treaſon, that it aymed at no leſs than the Deſtruction of the whole State at one blaſte; that the Contrivers were all Papiſts; that the pryme Hope of their Support was in the Engliſh Forces that ſerved the Archdukes, for which divers Captains there were prepared; he muſt needs conceive the King here to be unworthy of the eminent Throne in which Almighty God hath placed him as a potent Monarche over ſoe many Kingdoms and People, […]

Cannon, charged with grape, laid the men as flat as a pavement, exactly as a mighty wind levels standing grain at one blast.