Hand (unit) radix numbering system, where a hand is four inches. The hand, sometimes also called a handbreadth or handsbreadth, is an anthropic unit, originally based on the breadth of a male human hand, either with or without the thumb, or on the height of a clenched fist. On surviving Ancient Egyptian cubit-rods, the royal cubit is divided into seven palms of four digits or fingers each. Five digits are equal to a hand, with thumb; and six to a closed fist. The royal cubit measured approximately 525 mm, so the length of the ancient Egyptian hand was about 94 mm. In
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