WAR 



stars, and situated immediately above 

 Aquila and Sagitta. 



VU'LPIKIN. Vulpinic acid. An acid 

 substance obtained from the evernia vul- 

 pina of Achard, or the lichen vulpinus of 

 Linnaeus. 



VU'LPINITE. A mineral substance 

 consisting of sulphate of lime and silica, 

 and occurring together with granular 

 foliated limestone at Vulpino in Italy, 



WAT 



where it Is employed for ornamental 

 works under the name of marmo bar- 

 dig Ho. 



VULTU'RID^. The Vulture tribe ; 

 a family of the Raptores, or rapacious 

 birds, characterized by their untoothed 

 beak, and by the moderate curvature of 

 their talons, as compared with the fal- 

 cons, and by their head and part of their 

 neck being destitute of feathers. 



w 



WACKE'. A simple trap rock nearly 

 allied to basalt, of which it may be con- 

 sidered as a soft and earthy variety. 

 Ure states that it never contains augite 

 or olivine ; sometimes it is vesicular, 

 presenting amygdaloidal cavities filled 

 with various substances. 



WA DD. A technical name for plum- 

 bago or black lead. Black wadd is an 

 ore of manganese found in Derbyshire, 

 remarkable for its property of taking fire 

 when mixed with lintseed oil. 



WA'GNERITE. A rare mineral, 

 formerly confounded with the Brazilian 

 topaz. It consists of the phosphoric and 

 the fluoric acids, magnesia, iron, and 

 manganese. It occurs at Salzburg in 

 small veins of quartz in clay-slate. 



WAKE OF A SHIP. A nautical 

 term denoting the smooth water which is 

 astern of a ship under sail. It serves to 

 show the way the ship makes : if the 

 wake be right astern, she makes her way 

 forward; if it be to leeward a point or 

 two, she falls to the leeward of her 

 course. A ship is said to stay to the 

 weather of her wake, when, in her stay- 

 ing, she is so quick, that she does not 

 fall to leeward upon a tack, but that 

 when she is tacked, her wake is to the 

 leeward ; and it is a sign that she feels 

 her helm very well, and is quick of steer- 

 age. 



WANING. Declining in power. The 

 term is applied to the moon, as decrea- 

 sing in her light, as she proceeds from the 

 full to the change. 



WARM-BLOODED ANIMALS. A 

 term applied to two classes of vertebrate 

 animals, viz. the mammals and the birds. 

 In these there are two hearts, perfectly 

 distinct from each other ; and a twofold 

 circulation, viz. that which takes place 

 in the lungs, called the pulmonic, and 

 that which takes place through the 

 872 



entire system, called the systemic circu- 

 lation. 



WARP. The deposit of muddy waters, 

 artificially introduced into low lands. In 

 the operation of warping, it is only ne- 

 cessary to produce a stagnation of the 

 water for a few hours to have a copious 

 deposit, leaving the water clear over it. 



WASH. A technical term for the 

 fermented liquor, of any kind, from 

 which spirit is intended to be distilled. 



WATER. Protoxide of hydrogen; a 

 liquid produced by the combustion of 

 oxygen and hydrogen, consisting of two 

 volumes of the latter to one volume of 

 the former gas, and of eight parts of the 

 former to one of the latter by weight. 



Water, oxygenated. Peroxide of hy- 

 drogen ; a liquid containing twice as 

 much oxygen as water, but less volatile, 

 having a metallic taste, and instantly 

 bleaching litmus and other organic co- 

 louring matters. 



WATER OF CRYSTALLIZATION. 

 That portion of water which combines in 

 a dry state with many substances, form- 

 ing an essential condition of their crys- 

 talline character. Salts which retain this 

 water so feebly, that it passes off on ex- 

 posure to the air, leaving the salt in a 

 pulverulent state, are termed efflorescent; 

 while those which have so great an affi- 

 nity for it, that their crystals attract more 

 of it from the air, and become dissolved 

 in it, are called deliquescent. 



WATER-CLOCK. Clepsydra. A cy- 

 lindrical vessel with its surface divided 

 by lines into portions which are to one 

 another as the odd numbers, 1, 3, 5, 7, 

 &c., taken backward. Supposing such 

 a vessel required six hours to empty 

 itself, let it be divided into 36 equal 

 parts ; then, beginning from the surface, , 

 take eleven of those parts for the first 

 hour, nine for the second, seven for the 



