Search results
Results from the WOW.Com Content Network
A modern military compass, with included sight device for aligning. A compass is a device that shows the cardinal directions used for navigation and geographic orientation. It commonly consists of a magnetized needle or other element, such as a compass card or compass rose, which can pivot to align itself with magnetic north.
Since the author describes having witnessed the use of a compass on a ship trip some forty years earlier, some scholars are inclined to antedate its first appearance in the Arab world accordingly. [24] Al-Qibjāqī also reports that sailors in the Indian Ocean used iron fish instead of needles. [65]
A compass, also commonly known as a pair of compasses, is a technical drawing instrument that can be used for inscribing circles or arcs. As dividers, it can also be used as a tool to mark out distances, in particular, on maps. Compasses can be used for mathematics, drafting, navigation and other purposes.
Rulers used in technical drawing are usually made of polystyrene. It is used for drawing lines and connecting points. Rulers come in two types according to the design of their edge. A ruler with a straight edge can be used with lead pencils and felt pens, whereas when a technical pen is used the edge must be grooved to prevent the spread of the ...
This sub-section is about paper making; for the writing material first used in ancient Egypt, see papyrus.. Paper: Although it is recorded that the Han dynasty (202 BC – AD 220) court eunuch Cai Lun (50 AD – AD 121) invented the pulp papermaking process and established the use of new materials used in making paper, ancient padding and wrapping paper artifacts dating from the 2nd century BC ...
At first, compasses were thought to point towards locations in the heavens, then towards magnetic mountains. A modern experimental approach to understanding the Earth's field began with de Magnete, a book published by William Gilbert in 1600. His experiments with a magnetic model of the Earth convinced him that the Earth itself is a large magnet.
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!
Tin and iron oxides are often used to give the stone a highly reflective exterior. Sculptures can be carved via either the direct or the indirect carving method. Indirect carving is a way of carving by using an accurate clay, wax or plaster model, which is then copied with the use of a compass or proportional dividers [1] or a pointing machine ...