148 



Reading Test-Card. A card containing reading matter set up in 

 various size type for testing the reading capacity of the 

 eye. [2, 21.] 



Recoil Dynamometer. An instrument to measure the recoil of 

 small arms. 



Recorder, Sunshine. See Sunshine Recorder. [2, 4, 5, 9, 10, 13, 



*. 15, 17, 21, 24, 25, 27.] 



Recording Ammeter. See Ammeter. 



Recording Densimeter. See Densimeter. [4, 21] 



Recording Galvanometer. See Galvanometer. [4, 16] 



Recording Pyrometer. See Pyrometer. 



Recording Voltmeter. See Voltmeter. 



Redwood Inflammable Gas or Vapour Detector. See Inflam- 

 mable Gas or Vapour Detector. [13, 15] 



Redwood Standard Oil Weight. See Oil Weight. [13, 15] 



Redwood's Standard Viscometer. See Viscometer. [13, 15, 17, 

 21] 



Redwood Water-Finder. See Water-Finder. [13, 15, 16] 



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



Reeves's Endless Tangent Screw. See Screw. [13, 21] 



Reeves's Tangent Micrometer. See Micrometer. [6] 



Reflecting Circle. An instrument for measuring altitudes and 

 angular distances. [2, 27] 



Reflecting Galvanometer. See Galvanometer. [4, 13, 16] 



Reflecting Goniometer. See Goniometer. [19] 



Reflecting Level. A simple form of level, sometimes called the 

 Burel Level after its inventor, Col. Burel. See Level. [13, 

 17, 21, 25, 27] 



Reflecting Microscope. See Microscope. 



Reflecting Telescope. See Telescope. 



Reflector. An optical instrument by which the rays proceeding 

 from a luminous or heated object are thrown back or 

 diverted in a given direction without being transmitted. [3] 



Reflector, Beale's Neutral Tint. An instrument to fit on the eye- 

 piece of a microscope, for drawing the magnified image. 

 [2, 3, 17, 20, 22, 26] 



Refracting Circle. An instrument provided with a quadrated 

 circle for measuring refi action. [13] 



Refracting Dial. See Dial. [13] 



Refractometer. An instrument for exhibiting and measuring 

 the refraction of light, i.e., determining the refractive index 

 of transparent substances. [2, 13, 14, 22] 



Refractometer. Pulfrich's pattern for investigating optical glass. 

 [14, 26] 



Refractometer. Thornoe's pattern for beer. [14, 26] 



Refractometer, Abbe. For liquids. [14] 



Refractometer, Butyro- and Oleo-. For the examination of 

 butter, lard, and oils. [14] 



