133 



Paget Deflector. A special form of compass deflector. [IS.] 



Paget Dipping Needle. A special form of dip needle (q.v.). [15,] 



Paget Star Globe. See Star Globe. [13, 16.] 



Pagoscope. A form of wet and dry bulb thermometer with dia- 

 gram to foretell in the early evening whether there will be a 

 frost during the following night. See also Hygrometer. [2, 

 15, 17, 20, 21, 26.] 



Paleophone. A writing telephone. 



Palinurus. A gimballed instrument with time and latitude 

 scales for use on board ship to ascertain the true course 

 without tables or calculations. [15.] 



Pancratic Eyepiece. See Eyepiece. 



Panograph, The Simplex. A device to assist in making a 

 panoramic sketch in correct proportion and perspective. 

 [21.] 



Pantagraph. A pantograph (q.v.). [2, 5, 6, 13, 15, 17, 20, 21, 

 24, 26, 27.] 



Pantascope. An optical apparatus for viewing pictures through 

 a magnifying glass. [15.] 



Pantochrometer. An instrument which is a combination of the 

 compass, sundial, and universal sundial. [13.] 



Pantograph. An instrument used in copying plans, maps, and 

 other drawings on the same or on a reduced or enlarged 

 scale. It consists of a series of levers pivoted together 

 having a tracing point and a pencil fixed to suitable points 

 on the levers. See also Plagiograph. [6, '10, 13, 15, 17, 21, 

 24, 25, 27.] 



Pantometer. An instrument for measuring angles for the deter- 

 mination of elevations, distances, etc. [6, 13.] 



Paper Scales. Used by draughtsmen. Made of paper in place 

 of wood. Board of Trade official set. [2, 5, 15, 17, 20, 21, 

 24, 26, 27.] 



Paper Weighing Balance. A weighing machine used by paper- 

 makers for ascertaining the weight per ream by weighing 

 one sheet. 



Parabola (Wenham's). A glass reflector of paraboloid shape 

 for reflecting oblique light upon a microscopic object from 

 below. [2, 3, 20, 22.] 



Parabolagraph, Inward's. An instrument founded on that 

 property of the parabola by virtue of which any point on it 

 must be equally distant from a point called the focus and 

 a line called the directrix. 



Parabolic Curves. A set of wood or metal curves for drawing 

 parabolas. [2, 15, 20, 21, 24, 25, 27.] 



Parabolic Illuminator. See Illuminator. [2, 3, 20, 22, 26.] 



Parabolic Mirror. A mirror, usually concave, the surface of 

 which is generated by the revolution of the arc of a para- 

 bola. [1, 3, 11, 26.] 



Paraboloid Condenser. See Condenser. [2, 3, 20, 22.] 



