GLOSSARY. 



11 



which a straight line drawn from 

 the eye to any object dips below 

 the horizon. 



Angle of direction. In mechanics, 

 the angle contained by the lines of 

 direction of two forces tending to 

 the same point. 



Angle of elevation. In trigonometry, 

 the angle formed by two straight 

 lines drawn in the same vertical 

 plane from the observer's eye, one 

 to the top of the object, the other 

 parallel to the horizon. 



Angle of incidence. The angle which 

 a body, or a ray of light, forms at 

 the surface on which it falls with 

 a perpendicular to that surface. 



Angle of inclination. The mutual 

 approach of two bodies, so as to 

 make an angle where their lines of 

 direction meet. 



Angle of polarization. In optics, the 

 angle of incidence of a reflecting 

 surface which, added to the cor- 

 responding angle of refraction, sup- 

 posing the ray to enter the medium, 

 would make up a right angle, or 

 90 degrees. 



Angle of position. In astronomy, the 

 angle contained by two great circles 

 passing through the earth, one per- 

 pendicular to the plane of the 

 ecliptic, the other to that of the 

 equator. 



Angle of reflection. The angle which 

 a body or a ray of light rebounding 

 from a surface makes with a per- 

 pendicular to that surface. 



Angle of refraction. In optics, the 

 angle which a ray of light passing 

 from one medium to another makes 

 with a perpendicular drawn through 

 the line of incidence. 



Angle, solid. An angle made by 

 more than two plane angles meeting 

 in a point, and not lying in the 

 same plane. 



Angle, spherical. An angle on the 

 surface of a sphere, contained within 

 the arcs of two intersecting cir- 

 cles. 



Angle, visual. In optics, the angle 

 formed in the centre of the eye by 

 lines drawn from the extremities of 

 an object. 



An'gular {Lat. an'gulus, a corner). 

 Having or relating to angles. 



An'gulate (Lat. an'gulus, an angle). 

 Having an angular shape. 



Anhelation (Lat. anhelo, I breathe 

 short). Short breathing ; pant- 

 ing. 



Anhy'drous (Gr. d, a, not; vtiup, 

 hudor, water). Free from water; 

 without water of crystallization. 



Animal (Lat. anima, life, breath). A 

 body having life, sensation, and vo- 

 luntary motion. 



Animarcule (Lat. animal, an animal; 

 ule, signifying smallness). An ani- 

 mal of very small size. 



Animal heat. The warmth which 

 animals possess in themselves. 



Animalisa'tion (Lat. animal, an ani- 

 mal). The art of imparting the 

 properties belonging to an animal, 

 or to animal structures ; a peopling 

 with animals. 



An'ion (Gr. dva, up ; Iwv, ion, going). 

 That substance which passes to the 

 anode in electrolysis. 



Anneal (Saxon on, on ; celan, to 

 burn). To heat glass, &c., for 

 the purpose of rendering it less 

 brittle. 



Annual (Lat. annus, a year). Oc- 

 curring every year. 



An'nelids (Lat. annel'lus, a little ring ; 

 Gr. eiSos, eidos, form). A class of 

 invertebrate animals, so called be- 

 cause apparently composed of rings, 

 including earth-worms and leeches. 



An'nular (Lat. annulus, a ring). 

 Shaped like a ring. 



Annula'ta (Lat. annulus, a ring). 

 Having rings : applied to a division 

 of the animal kingdom, including 

 invertebrates having the body ar- 

 ranged in rings. 



An' ode (Gr. ava, ana, up ; &$os, hod'os, 

 a way). The way by which elec- 

 tricity enters substances. 



An'odyne (Gr. o, a, not ; oSwrrj, odu'ne, 

 pain). Relieving pain. 



Anom'alous (Gr. d, a, not ; 6fta\os, 

 hom'aloSy level, or equal). De- 

 parting from a general rule ; 

 irregular. 



Anom'aly (Gr. a, a, not ; <5,uaAos, 

 hom'alos, level or equal). Irregu- 



