‹‹‹ Vitr. 10.8.4 | Table of Contents | Vitr. 10.8.6 ›››
5Thus, when the levers are raised, the piston-rods are depressed to the bottom of the barrel, and the dolphins turning on their pivots, suffer the valves attached to them to descend, thus filling with air the cavities of the barrels. Lastly; the pistons in the barrels being alternately raised and depressed with a quick motion, cause the valves to stop the upper holes: the air, therefore, which is pent, escapes into the pipes, through which it passes into the wind-chest, and thence, by its neck, to the box.
5So, when the levers are raised, the elbows draw down the bottoms of the cylinders as far as they can go; and the dolphins, which are mounted on joints, let the cymbals fall into the cylinders, thus filling the interiors with air. Then the elbows, raising the bottoms within the cylinders by repeated and violent blows, and stopping the openings above by means of the cymbals, compress the air which is enclosed in the cylinders, and force it into the pipes, through which it runs into the regulator, and through its neck into the windchest. With a stronger motion of the levers, the air is still more compressed, streams through the apertures of the cocks, and fills the channels with wind.