TABLE OF CONTENTS Units of Measurement Distances are usually measured in feet and tenths, hun-dredths, and (for accurate work) thousandths of feet (meters, centimeters, and millimeters). For many older surveys, distances were measured in chains and links. A chain is 66 ft (20.1 m) in length and is divided into 100 links, each 7.92 in (201.2 mm) long. The metric system, in which the unit of distance is the meter and its decimal fractions or multiples, is in use in most countries and is expected to replace the English system of measurement in the United States. See Chap. 1 for conversion factors.
Four methods used for the direct measurement of distance are pacing, stadia reading, taping, and electronic distance recording.
Pacing. Pacing is a rapid means of checking more accurate measurements of distance. The precision of pacing under average conditions is from 1:100 to 1:200.
Stadia Reading. The use of stadia furnishes a rapid method of determining distances with a fair degree of accuracy. Under average conditions, a precision of from 1:300 to 1:1000 can be obtained. [1]
Measurement with Tape. The most commonly used method of determining distance is by measurement with a tape. Steel tapes, ranging in length from 50 to 300 ft (15.2 to 91.4 m), are generally used, but tapes of other materials may be used where accuracy is not essential. The precision of a tape measurement depends on the degree of refinement with which the measurement is...
