Page 79 - Moving the Earth_ The Workbook of Excavation
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SURVEYS AND MEASUREMENTS
SURVEYS AND MEASUREMENTS 2.29
The laser is now rechecked for level and for correct grade setting, and another check of the align-
ment of the two instruments is made. The level vial should be checked intermittently during the work.
In-Pipe Mounting. Many lasers are equipped with mountings that permit insertion in a pipe, or
if the pipe is very small, just outside one end and looking through. See Figs. 2.26 and 2.27. The
support member is a square bar with a cross piece at one end and a threaded adjustment at the other.
FIGURE 2.26 In-pipe mounting.
FIGURE 2.27 In-pipe target and remote control device. (Courtesy of AGL Lasers.)
