54 



Alcoholometer. A hydrometer (q.v.} graduated to indicate the 

 alcoholic strength of spirits. [5, 13, 15, 17, 21.1 



Aldis Spherometer. See Spherometer. [1.] 



Alembic. An old from of retort used for distillation. 



Aleurometer. An instrument to measure the elasticity of the 

 gluten of flour. 



Alidade. A rule with telescope or sights at its ends for use 

 on a Surveyor's Plane Table to give the direction of any 

 object from a given point. [2, 6, 13, 15, 17, 18, 20, 24, 25, 

 27, 28.] 



Alidade, Reeves's Distance-Finder. See Distance-Finder. [28.] 



Alignment Tester. An instrument for testing the exact align- 

 ment of machine-tool beds, etc. [4.] 



Alkalimeter. (i) An instrument to ascertain the strength of 

 alkalies or the quantity of alkali in a mixture. (2) A 

 dropping-bottle for delivery of small quantities of re-agent, 

 whether chemical or bacteriological. [13, 17, 21.1 



Alkalimeter, Schuster's. 



Altazimuth. An instrument for measuring altitudes and azi- 

 muths. Generally a telescope provided with altitude and 

 azimuth movements. [3, 6, 9, 13, 15, 17, 18, 20, 21, 25, 26, 

 27.] 



Alti-hyphydroscope. A submarine periscope (q.v.) modified so as 

 to give views not only of the sea surface, but of elev,ted 

 objects. [26.] 



Altimeter. An instrument for taking altitudes, as a quadrant 

 sextant, theodolite, etc. Also used to describe an aneroid 

 barometer, which indicates heights. [4, 13, 15, 16, 17, 20, 

 21, 25, 27.] 



Altiscope. An arrangement of lenses and mirrors or prisms 

 which enables a person to observe an object in spite of 

 intervening objects. See also Periscope. [16] 



Altitude Recorder. A form of barograph (q.v.) for recording the 

 varying and maximum altitude attained. 



Amblyoscope. An instrument for testing muscular insufficiencies 

 of the eyes in strabismus. [2] 



Ambulator. An instrument used by Surveyors for measuring 

 linear distances over the ground. It consists of an accurately 

 turned wheel with handle. Attached to the axis is a box 

 containing gearing and dial by means of which the distance 

 over which the wheel is pushed is registered. [16, 17, 21.] 



Amici Prism. See Prism. [2, 3, 20, 26] 



Ammeter. A galvanometer (q.v.) graduated for the measurement 

 of electric currents in terms of amperes. See also Thermo- 

 Ammeter. 



Ammeter, Recording. A form' of ammeter in which the current 

 is automatically recorded. 



Ammonia Gauge. A form of pressure gauge made of steel used 

 in the measurement of the vapour pressure of ammonia. 

 [5, 6. 



