The boy swung the muzzle of the gun around again. It was strange, thinking it over, to be so surrounded by air, separated from other things by yards of air. When he aimed the gun, on the other hand, the air was a straight invisible line drawn tight from the mouth of the rifle to the target, to the hawk flying up there in the sky with wings that did not seem to move. When he pressed the trigger, the air was still as empty and transparent as before, but up there, at the other end of the line, the hawk was folding its wings and dropping like a stone. From the open bolt floated the good smell of gunpowder.
-- Italo Calvino, "The Crow Comes Last"