Search results
Results from the WOW.Com Content Network
In many measurement systems based on former English units, the link has remained fixed at 0.66 feet, therefore 0.22 yards or 7.92 inches; it is the absolute length of the yard that has varied. A rare remaining application of the link is in the service of some surveying in the United States, which relates to the definition of the survey foot.
The metric rod has major numbered graduations in meters and tenths of meters (e.g. 18 is 1.8 m - there is a tiny decimal point between the numbers). Between the major marks are either a pattern of squares and spaces in different colours or an E shape (or its mirror image) with horizontal components and spaces between of equal size. In both ...
The term stadia comes from a Greek unit of length Stadion (equal to 600 Greek feet, pous) which was the typical length of a sports stadium of the time. Stadiametric rangefinding is used for surveying and in the telescopic sights of firearms , artillery pieces , or tank guns , as well as some binoculars and other optics.
Once this is done, the slope may be read from the scale. Because the level is typically held at the surveyor's eye-height, it is common to use the face of a second surveyor of similar height as a target. If the second surveyor is not the same height, the approximate location of eye-height must be noted (i.e. chin, nose, top of head).
A quarter chain, or 25 links, measures 16 feet 6 inches (5.03 m) and thus measures a rod (or pole). Ten chains measure a furlong and 80 chains measure a statute mile. [1] Gunter's chain reconciled two seemingly incompatible systems: the traditional English land measurements, based on the number four, and decimals based on the number 10.
The rod, perch, or pole (sometimes also lug) is a surveyor's tool [1] and unit of length of various historical definitions. In British imperial and US customary units, it is defined as 16 + 1 ⁄ 2 feet, equal to exactly 1 ⁄ 320 of a mile, or 5 + 1 ⁄ 2 yards (a quarter of a surveyor's chain), and is exactly 5.0292 meters.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
The level must be horizontal to get a valid measurement. Because of this, if the horizontal crosshair of the instrument is lower than the base of the rod, the surveyor will not be able to sight the rod and get a reading. The rod can usually be raised up to 25 feet high, allowing the level to be set much higher than the base of the rod.