6 4 



Bow Compass. Drawing compasses (q.v.) for describing small 



curves or circles. [2, 5, 6, 9, 13, 15, 17, 20, 21, 24, 25, 26, 27.] 

 JSow Fen. A drawing instrument for describing circles in ink. 



12, 6, 9, 13, 15, 17, 20, 21, 24, 25, 26, 27.] 

 Bow Pencil. A drawing instrument for describing circles in 



pencil. [2, 6, 9, 13, 15, 17, 20, 21, 24, 25, 26, 27.] 

 Box Photometer. See Photometer. [2, 3.] 

 Box Sextant. See Sextant. [2, 3, 5, 6, 9, 10, 13, 15, 16, 17, 20, 21, 



24, 25, 26, 27, 28.] 

 Boxwood Compasses. For drawing circles and curves with 



chalk on the blackboard for lecture purposes. [6, 13, 15, 



20, 21, 27.] 



Boys's Calorimeter. See Calorimeter. [19.] 



Boys's Radio-Micrometer. See Radio-Micrometer. 14.] 



Brearley Curve Tracer. See Curve Tracer. 14.] 



Broca Galvanometer. See Galvanometer. [4, 19] 



Brook's Curves. Flexible steel bands adjustable to any form of 



curve for draughtsmen's use. [2, 5, 13, 15, 21, 24, 25, 27.] 

 Brooke's Sounding Apparatus. See Sounding Apparatus. [13, 



15.] 

 Browning's Pocket Spectroscope. See Spectroscope. {2, 10, 17, 



20.] 



Browning's Spectroscope. See Spectroscope. [17, 20.] 

 Bryan's Osculating Table. See Oscillating Table. [19.] 

 Bullet Compasses. See Compasses. 

 Bull's-Eye Condenser. See Condenser. [2, 3, 8, 9, 10, 17, 20, 



21, 22, 26.] 



Bunsen Burner. A gas jet fitted with an adjustable air ad- 

 mission so that gas and air are mixed in such proportions 

 that they burn with a non-luminous flame of high temper- 

 ature. Used in incandescent gas burners. [2. 10.] 



Bunsen's Photometer. See Photometer. [2, 10.] 



Burel Level. See Level. 



Burette. An apparatus for delivering measured quantities of 

 liquid or gas received or discharged. It consists essentially 

 of graduated glass tube and stop-cock. [2, 13, 17, 21.] 



Burgess's Colorimeter. See Colorimeter. 



Burner. See Bunsen Burner and Meker Burner. [2, 10.] 



Burnet Bearing Clamping Compass. See Compass. [15, 28] 



Burrough's Adding Machine. See Adding Machine. [20.] 



Butyrometer. An instrument for determining the amount of 

 fatty matter or butter contained in milk. [2, 21, 26.] 



Butyro-Refractometer. See Refractometer. 



Cadran. An instrument with a graduated disc by means of 



which angles of gems are measured in the process of cutting 



and polishing. 

 Calcimeter. An instrument for making volumetric analyses of 



bone dust, meerschaum, and other substances containing 



lime. 



