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microscope

(Encyclopedia)CE5 Compound microscope microscope, optical instrument used to increase the apparent size of an object. The electron microscope, which is not limited by the powers of optical lenses and light,...

drill, tool

(Encyclopedia)drill, tool used to create a hole, usually in some hard substance, by its rotary or hammering action. Many different tools make up the drill family. The awl is a pointed instrument used for piercing s...

watch

(Encyclopedia)watch, small, portable timepiece usually designed to be worn on the person. Other kinds of timepieces are generally referred to as clocks. At one time it was generally believed that the first watches ...

needle

(Encyclopedia)needle, implement of metal or other material used to carry the thread in sewing and in various forms of needlework and manufacturing. The earliest needles were merely awls or punches. Stone, bone, ivo...

needlework

(Encyclopedia)needlework, work done with a needle, either plain sewing, mending, or ornamental work such as embroidery, quilting, smocking, hemstitching, fagoting, some kinds of lace making (see lace), patchwork, a...

Napier, John

(Encyclopedia)Napier, John nāˈpēr, nəpērˈ [key], 1550–1617, Scottish mathematician and theologian. He invented logarithms and wrote Mirifici logarithmorum canonis descriptio (1614), containing the first log...

rectifier

(Encyclopedia)rectifier, component of an electric circuit used to change alternating current to direct current. Rectifiers are made in various forms, all operating on the principle that current passes through them ...

scale, in cartography

(Encyclopedia)scale, in cartography, the ratio of the distance between two points on a map to the real distance between the two corresponding points portrayed. The scale may be expressed in three ways: numerically,...

score

(Encyclopedia)score, in musical notation, manuscript or printed music in which the various parts are placed one above the other so that notes that are to be played simultaneously are in vertical alignment. Early po...

cross-laminated timber

(Encyclopedia)cross-laminated timber (CLT), manufactured wood panels that consist of layers of boards glued together under pressure with the grain of the boards in one layer running perpendicular to the grain in ad...