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abacus, in mathematics

(Encyclopedia)CE5 Chinese abacus: Numbers are represented by moving beads to the central crossbar. abacus ăbˈəkəs, əbăkˈ– [key], in mathematics, simple device for performing arithmetic calculations. Th...

bur

(Encyclopedia)bur or burr, popular name for fruits that have barbed, pointed, or rough outgrowths. By clinging to the fur or hair of animals and the clothing of man they are transported from the parent plant, often...

inductor

(Encyclopedia)inductor, electric device consisting of one or more turns of wire and typically having two terminals. An inductor is usually connected into a circuit in order to raise the inductance to a desired valu...

torsion balance

(Encyclopedia)torsion balance, instrument used to measure small forces. It is based on the principle that a wire or thread resists twisting with a force that is proportional to the stress. The torsion balance consi...

Gates, John Warne

(Encyclopedia)Gates, John Warne, 1855–1911, American financier and promoter, known as Bet-a-Million Gates, b. near Chicago. He discovered a market for wire fencing on the Western plains, began the manufacture of ...

quarrying

(Encyclopedia)quarrying, open, or surface, excavation of rock used for various purposes, including construction, ornamentation, road building, and as an industrial raw material. Rock that has been quarried is commo...

harpoon

(Encyclopedia)harpoon härpo͞onˈ [key], weapon used for spearing whales and large fish. The early type was a flat triangular piece of metal with barbed edges and a socket for attaching a wooden handle, to the end...

solenoid

(Encyclopedia)solenoid sōˈlənoidˌ [key], device made of a long wire that has been wound many times into a tightly packed coil; it has the shape of a long cylinder. If current is sent through a solenoid made of ...

electromagnet

(Encyclopedia)CE5 Electromagnet electromagnet, device in which magnetism is produced by an electric current. Any electric current produces a magnetic field, but the field near an ordinary straight conductor is ...

brome grass

(Encyclopedia)brome grass, common name for any plant of the genus Bromus, chiefly large, coarse grasses of a weedy nature; some, however, are useful as forage, and others are cultivated for decoration. Some of the ...