IIOR 



HOR 



the margin of rivers in the Middle 

 States, rising twenty to forty feet. 



The term hornbeam, or ironwood, 

 is also applied to the Oxtrya Vvrgin- 

 iaca, a tree of twenty to forty feet 

 high, of the same family, found in the 

 Southern States. The wood is as 

 serviceable as that of the hornbeam. 



HORNBLEND. A dark green or 

 black mineral, massive or crystal- 

 lized in prisms, of glassy lustre, and 

 readily scratched by a knife. It is 

 very abundant in primary, transition, 

 and trap formations, and consists of 

 silica, 46 ; lime and magnesia, 34 ; 

 iron, from 4 to 7 ; alumina, &c., 13 

 per cent. It forms the basis of nu- 

 merous minerals, and is found in sev- 

 eral varieties, as augite, amphibole, 

 pargasite, tremolite, actinolite. 



Hornblend slate and schist are 

 transition rocks, consisting of a mix- 

 ture of hornblend, quartz, and some- 

 times feldspar. A soil formed from 

 these rocks is necessarily rich, from 

 containing lime, magnesia, potash, 

 clay, and sand. The crystals also 

 occur in siennite, or Boston granite. 

 Greenstone, the common ingredient 

 of dikes, is a mixture of hornblend 

 and feldspar, varying but little from 

 trap. Soils rich in hornblend have a 

 greenish colour. 



HORNBUG. The beetles of the 

 genus Lucanus, or stag beetles, espe- 

 cially L. caprcolus. The grubs live 

 in the trunks and roots of old trees. 



HORN DISTEMPER. A disease 

 of the horns of oxen, especially cows, 

 in which an accumulation of pus 

 takes place in the pith ; the treat- 

 ment is, to let it out by boring into 

 the horn, two inches from the head, 

 with a small gimlet. The animal 

 affected first exhibits the signs of a 

 cold, the eyes become dull, the ap- 

 petite diminishes, the creature lan- 

 guishes and lies down ; but it is also 

 occasionally attended with symptoms 

 of diseased brain ; the animal tosses 

 his head and groans much. 



HORN PITHS or FLINTS. 

 These answer in manuring for bones, 

 having a composition nearly identical 

 with bones, namely, gelatin and fat, 

 86 ; bone earth, 54 per cent. : they de- 

 384 



cay more rapidly from their porous 

 structure. They are difficult to crush 

 in the common bone mil), but may be 

 broken by a heavy bark mill, or dis- 

 solved in strong acid. They are much 

 used for the extraction of size and 

 glue. 



HORNET. Vespa maculata, the 

 American species. They build a 

 globular nest of a substance like pa- 

 per upon branches of trees, &c. Its 

 sting is painful, but may be allayed 

 by oil, with a little hartshorn. It 

 preys upon fruit, flies, and is very de- 

 structive to bees. The European 

 species is V. crabro. 



HORNSTONE. A flinty mineral. 

 Chert, also, is known by this name. 

 Hornstone is wrought in stones for 

 crushing flints in potteries ; it also 

 forms a good hone. The varieties 

 are variously coloured, gray, white, 

 red, and dark greenish ; it is infusi- 

 ble before the blow-pipe, and contains 

 76 per cent, silica, with 13 alumina, 

 colouring oxide, and water. 



HORSE. "Nahiral Histmy and 

 Deyitition of the Horse. — The native 

 country of the horse is unknown. 

 From very remote periods he has 

 been found in almost every part of 

 the Old World, but his appearance 

 on the continents and the islands of 

 the New World, whether of the At- 

 lantic or Pacific Ocean, is of com- 

 paratively recent date. Everywhere 

 he is recognised as the most useful 

 of the servants of man, and he yields 

 in intelligence to the dog alone. If 

 he differs in ditTerent countries in 

 form and in size, it is from the in- 

 fluence of climate and cultivation ; 

 but otherwise, from the war-horse, 

 as he is depicted on the friezes of an- 

 cient temples, to the stately charger 

 of Holstein and of Spain, or from the 

 fleet and beautiful Arabian to the di- 

 minutive Shetlander, there is an evi- 

 dent similarity of form and destina- 

 tion which clearly stamps his common 

 origin. 



" He is naturally, and of choice, an 

 herbivorous and granivorous animal. 

 His thin and muscular lips, his firm 

 and compressed mouth, and his sharp 

 incisor teeth, are admirably adapted 



