Hand (unit) divided by four, then the remainder is added after the radix point. Thus, a horse that measures 60 inches is 15 hands high (15 x 4 = 60) and a horse halfway between 15 and 16 hands is 15.2 hands, or 62 inches tall (15 x 4 + 2 = 62) Because the subdivision of a hand is a base 4 system, a horse 64 inches high is 16.0 hands high, not 15.4. A designation of "15.5 hands" is not halfway between 15 and 16 hands, but rather reads 15 hands and five inches, an impossibility in a base 4
Tree height measurement measure log length. Some clinometers are hand held devices used to measure angles of slopes. The user can sight to the top of a tree using such a clinometer and read the angle to the top using a scale in the instrument. Topographic Abney levels are calibrated so when read at a distance of from the tree, the height to the tree above eye level can be directly read on the scale. Many clinometers and Abney levels have a percent-grade scale that gives 100 times the tangent of the angle. This scale gives the tree height in feet directly when