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actinometer

(Encyclopedia)actinometer ăkˌtənŏmˈətər [key], instrument used to measure the heating power of radiation. Actinometers are used chiefly in meteorology to measure solar radiation as transmitted directly by th...

Rittenhouse, David

(Encyclopedia)Rittenhouse, David, 1732–96, American astronomer and instrument maker, b. near Germantown, Pa., self-educated. A clockmaker by trade, he developed great skill in the making of mathematical instrumen...

periscope

(Encyclopedia)periscope pĕrˈĭskōp [key] [Gr.,=view around], instrument to enable a person to see objects not in his direct line of vision or concealed by some intervening body. Its essential parts are a tube, p...

stamp tax

(Encyclopedia)stamp tax, method of collecting duties on certain transactions by means of a validating stamp attached to the taxable instrument, which may be a judicial act, a commercial document, a transfer of prop...

weather vane

(Encyclopedia)weather vane or wind vane, instrument used to indicate wind direction. It consists of an asymmetrically shaped object, e.g., an arrow or a rooster, mounted at its center of gravity so it can move free...

Morse, Samuel Finley Breese

(Encyclopedia)Morse, Samuel Finley Breese, 1791–1872, American inventor and artist, b. Charlestown, Mass., grad. Yale, 1810. He studied painting in England under Washington Allston and achieved some success. He r...

galvanometer

(Encyclopedia)CE5 Galvanometer galvanometer gălˌvənŏmˈətər [key], instrument used to determine the presence, direction, and strength of an electric current in a conductor. All galvanometers are based upo...

concerto

(Encyclopedia)concerto kənchârˈtō [key], musical composition usually for an orchestra and a soloist or a group of soloists. In the 16th cent. concertare and concertato implied an ensemble, either vocal or instr...

radiometer

(Encyclopedia)radiometer rāˌdēŏmˈətər [key], instrument for detection or measurement of electromagnetic radiation; the term is applied in particular to devices used to measure infrared radiation. One of the ...

Jodrell Bank Observatory

(Encyclopedia)Jodrell Bank Observatory jôdˈrəl [key], observatory for radio astronomy located at Jodrell Bank, Macclesfield, England. Founded in 1945 on the site of a botanical experiment station, it is administ...