Absorption by quicklime or cement of moisture and carbon dioxide from the atmosphere, causing the material to change its chemical

A device for regulating the quantity of air being mixed with gas for combustion.

A ventilating shaft; a roofless enclosed area within a building or between buildings; may have openings such as windows.

An apparatus for separating ground-up materials pneumatically into various sizes.

The legal property right for use of the space above a specified elevated plane; usually includes the right to ground

A valve, usually manually operated, which is used to release air from a water pipe or fitting.