A relatively permanent object used to identify the location of a survey station or corner.

A device for indicating the horizon, as a bubble, pendulum or the flat surface of a liquid.

Light provided by an artificial source which has a spectral distribution approximating that of natural daylight at a correlated color

A structure which permits relative motion to occur between its parts (e.g., by means of one or more sliding or

A drop chute, for a falling stream of concrete, which consists of a vertical succession of tapered metal cylinders, so