GLOSSARY. 



149 



Pyogen esis (Gr. irvos, pu os, pus ; 

 yevea-is, genesis, a production). 

 The formation of pus. 



Pyohae'mia. See Pyaemia. 



Pyramid (Generally said to be from 

 Gr. irvp, pur, fire ; but uncertain). 

 A solid body, having a plane base, 

 with any number of sides and 

 angles, the sides consisting of 

 planes meeting in a vertex or point. 



Pyretol'ogy (Gr. irvperos, pu'retos, a 

 fever ; \oyos, log'os, a discourse). 

 A treatise on fevers, or the doctrine 

 of fevers. 



Pyrex'ia (Gr. irvp, pur, fire ; eiy, 

 hexis, a holding). A state of fever. 



Py'riform (Lat. pj/rus, a pear ; for'- 

 ma, shape). Shaped like a pear. 



Pyri'tes (Gr.' irvp, pur, tire). Fire- 

 stone ; a name given to the native 

 sulphurets of copper and iron. 



Pyro- (Gr. irvp, pur, fire). A prefix 

 in compound words, signifying fire ; 

 in chemistry, signifying that the 

 substance named has been formed 

 at a high temperature. 



Pyrog'enous (Gr. irvp, pur, fire ; 

 *ytvva.(a, genna'o, I produce). Pro- 

 duced by fire. 



Pyrolig'neous or Pyrolig'nous (Gr. 

 irvp, pur, fire ; Lat. lig'num, wood). 

 Procured by the distillation of 

 wood ; applied to the acid liquor 

 which passes over with the tar 

 when wood is subjected to destruc- 

 tive distillation. 



Pyrolig'nite. A salt formed by the 

 combination of pyroligneous acid 

 with a base. 



Pyrol'ogy (Gr. irvp, pur, fire ; \oyos, 

 log' os, a discourse). A treatise on 

 heat. 



Pyroma'nia (Gr. irvp, pur, fire ; 

 u.a.via, ma'nia, madness). An in- 

 sane desire for burning houses, &c. 



Pyrom'eter (Gr. irvp, pur, fire ; u- 

 rpov, met' ran, a measure). An 

 instrument for measuring the ex- 

 pansion of bodies by heat ; or for 

 measuring degrees of heat above 

 those indicated by the mercurial 

 thermometer. 



Pyromor/phous (Gr. irvp, pur, fire ; 

 jUop^Tj, morphe, form). Having the 

 property of being crystallised by fire. 



Pyroph'orous (Gr. irvp, pur, fire ; 

 (pepoa, pher'o, I bear). A substance 

 which takes fire on exposure to the 

 air, or which maintains or retains 

 light. 



Pyrophos'phate. A compound of 

 pyrophosphoric acid with a base. 



Pyrophosphor'ic (Gr. irvp, pur, fire ; 

 phosphor'ic acid). An acid pro- 

 cured by exposing phosphoric acid 

 to heat, and differing from it in 

 uniting with two equivalents of base. 



Py / roscope(Gr. irvp, pur, fire ; o-woTreco, 

 skop'eo, I view). An instrument 

 for measuring the intensity of heat 

 radiating from a fire. 



Pyro'sis ((lT.irvpoc<ns,puro'sis, aburn- 

 ing). A diseased state of the stomach 

 attended with severe pain and the 

 ejection of a large quantity of watery 

 fluid ; water- brash. 



Pyrotech'nic (Gr. irvp, pur, fire ; 

 rex^n, techne, art). Relating to 

 the art of making fireworks. 



Fyroxyl'ic (Gr. irvp, pur, fire; |uAoi>, 

 xulon, wood). A term applied to a 

 spirit produced by the destructive 

 distillation of wood. 



Pyrox'ylin (Gr. irvp, pur, fire ; v\ov, 

 xulmi, wood). Gun-cotton. 



Pyr'rhonism (Pyrrho, the founder of 

 a sect). Scepticism: universal doubt. 



Pyxid'ium (Lat. pyx'is, a small box). 

 In botany, a fruit, consisting of a 

 capsule with a lid. 



Quad'ra (Lat., a square). In archi- 

 tecture, a square frame or border. 



Quad'rangle (Lat. quat'uor, four; 

 an'gulus, an angle). A figure 

 having four sides and four angles. 



Quad'rant (Lat. quad'ro, I make 



square). A fourth part ; the fourth 

 part of the circumference of a circle, 

 or 90 degrees ; also the space in- 

 cluded between the are and two 

 radii drawn from its extremities to 

 the centre of the circle ; an instru- 



