196 



GLOSSARY. 



V. 



Vac'cinate (Lat. vacca, a cow). To 

 introduce the cowpox into the hu- 

 man being, as a preventive of 

 small -pox. 



Vac'uum (Lat. vacuus, empty). Space 

 devoid of all matter or substance. 



Vagi'na (Lat. a sheath). In botany, 

 the sheath formed by a petiole 

 round a stem, as in grasses. 



Vagi'nate (Vagi'na). Sheathed. 



Vaginipen'nous (Lat, vagi'na, a 

 sheath ; penna, a wing). Having 

 the wings enclosed in a sheath. 



Vallec'ula (Lat. val'lis, a valley ; u'la, 

 denoting smallness).. In botany, 

 the interval between the ribs in 

 the fruit of umbelliferous plants. 



Val'vate (Lat. val'vce, folding doors). 

 Having valves ; opening by valves : 

 applied to sestivation and verna- 

 tion, when the leaves in the flower- 

 bud or leaf-bud are applied to each 

 other by their margins only. 



Valve (Lat. val'vce, folding doors). 

 In anatomy, a fold of membrane in 

 a tube or vessel preventing the 

 backward flow of fluids. 



Val'vule (Valve). A little valve. 



Vanishing Point. In perspective, 

 the point at which an imaginary 

 line, passing through the eye of 

 the observer parallel to any original 

 line, cuts the horizon. 



Vaporiza'tion (Va'por). The rapid 

 conversion of a fluid into a vapour 

 by heat. 



Va'riable (Lat. va'rius, changing). In 

 the differential calculus, applied 

 to quantities which are subject to 

 continual increase or diminution. 



Va'riable Elements. In astronomy, 

 a method of viewing the effects of 

 disturbing forces acting on a body 

 moving in an elliptic orbit, which is 

 supposed from time to time to 

 change its position, form and mag- 

 nitude in a minute degree. 



Variation (Lat. va'rius, changing). 

 An 'alteration or partial changes ; in 

 arithmetic and algebra, applied to 



the different arrangements that can 

 be made of any number of things, 

 a certain number being taken to- 

 gether ; in astronomy, the inequality 

 in the moon's apparent motion, 

 which is greatest at conjunction and 

 opposition, and least at the quad- 

 ratures. 



Varicella. The chicken-pox. 



Varicose (Lat. va'rix, a swollen vein). 

 Enlarged ; applied to the veins 

 when they are distended and pre- 

 sent a knotty appearance. 



Vari'ety (Lat. va'rius, changing). In 

 natural history, a plant or animal 

 differing from the rest of its species 

 in some accidental circumstances, 

 which are not permanent or con- 

 stant, and are produced by the ope- 

 ration of such causes as climate, 

 food, cultivation, &c. 



Vari'ola (Lat. va'rius, spotted). The 

 small-pox. 



Vari'olous (Vari'ola). Relating to 

 the small-pox. 



Varix (Lat.). An uneven dilatation 

 of a vein. 



Vas'cular (Lat. vas'culum, a little 

 vessel). Belonging to vessels ; con- 

 sisting of, or containing vessels. 



Vas'cular System. The collective 

 name for the blood-vessels. 



Vasculif'erous (Lat. vas'culum, a 

 little vessel ; fei-'o, I bear). In 

 botany, applied to plants which have 

 the seed-vessels divided into cells. 



Va'sifonn (Lat. vas, a vessel ; forma, 

 shape). Resembling vessels ; ap- 

 plied to a vegetable tissue called 

 dotted vessels. 



Vegetable (Lat. vey'eo, I grow). A 

 body having life, but without sen- 

 sation or voluntary motion. 



Veg'etate (Lat. veg'eo, I flourish). 

 To grow, like plants. 



Vegeta'tion ( Veg'etate). The process 

 of growing like plants. 



Veg'etative ( Vegetate). Having the 

 power of growing, or of producing 

 growth in plants. 



