On the removal of any plug, this wire gauze prevented the sand from flowing with the water into the well; but while the finer particles of sand remained in the neighbourhood of the orifice, the flow of water through the contracted area was very small.
Observed through this the structure of some wire gauze just disappeared at a distance from the eye equal to 17 in., the gauze containing 46 meshes to the inch.
The disk 32 operates the wire gauze screens for equalizing the brightness of the two stars under observation.
The open-air education was originally proposed by Chavannes of Lausanne, and largely carried out in the canton of Vaud by Roland, who reared his worms on mulberry trees enclosed within " manchons " or cages of wire gauze and canvas.
Of the cast-iron cylinders forming the well was provided with about 660 small orifices lined with gun-metal tubes or rings, each armed with numerous thicknesses of copper wire gauze, and temporarily closed with screwed plugs.