HORTICULTURE. 



HOVEN. 



of a deep glaucous green, from one to two feet 

 high, cylindrical, uniformly and rather copi- 

 ously furrowed, the furrows minutely toothed 

 and of a strong hardness. This species is 

 wholesome to horses, and is eaten by them ; 

 but it is hurtful to cows and disagreeable to 

 sheep. That eminent chemist, Sir H. Davy, 

 first detected a quantity of pure silex in the 

 furrowed cuticle of this plant, which accounts 

 for its power, as a file, in polishing wood, 

 ivory, or even brass. This purpose it has long 

 served in England, under the name of Dutch 

 rushes, being usually imported from Holland, 

 and is chiefly employed by turners and cabinet- 

 makers to polish their work, as well as by 

 dairy-maids for cleaning pails and other wood- 

 en utensils. So wheat-straw, whose cuticle 

 contains the same earth in an impalpable 

 state, like others of the natural family of 

 grasses, is used, when burnt, to give the last 

 polish to marble. 



Mr. Nuttall observes that this species is very 

 abundant on the banks of the Missouri below 

 the Platte, and called " Rushes." It is, he says, 

 found to be injurious to horses which feed 

 upon it for any considerable length of time. 



7. Variegated rough horsetail (E.varit . 

 is found in wet, sandy ground in Scotland and 

 Ireland. The whole plant is smaller and much 

 more slender than the last The fibres ..f the 

 root of this curious little species are remark- 

 ably woolly, like those of grasses that grow in 

 loose sand. The sheaths which crown the 

 joints are lax, with lanceolate teeth. The 

 catkin is ovate, acute, blacker than E. hyemale, 

 with a more slender stem. (Eng. Flor. iv. 335 

 311; WMirKs Dom, Enc yc.} 



HORTICULTURE (Lat. hortus, a garden, 

 and co/o, I cultivate). The culture of the 

 kitchen garden and orchard. The chief dif- 

 ference between horticulture and agriculture 

 is, that in the former art the culture is per- 

 formed by manual labour in a comparatively 

 limited space, called a garden; while in the 

 latter it is performed jointly by human and 

 animal labour in fields, or in an extensive tract 

 of ground called a farm. 



HORTUS SICCUS. A collection of dried 



S'ants preserved in books or papers. See 

 KRUAL. 



HOT-BEDS. In gardening, are made either 

 with fresh horse-dung, or tanner's bark, and 

 covered with glasses to protect them from the 

 severity of the wind and weather. It is very 

 important in making hot-beds not to raise the 

 temperature too high, as the plants become 

 scorched. See KITCHEN GARDEN, and FORCING 

 PITS. 



HOT-HOUSE. A general term for the glass 

 structures used in gardening and including 

 STOVES, GREENHOUSES, ORANGERIES and CON- 

 SERVATORIES. See these heads. 



HOT WALLS. In gardening, walls for the 

 growth of fruit trees, which are built with flues 

 or other contrivances for being heated in 

 severe weather, RO as to facilitate the ripening 

 of the wood or the maturity of the fruit. The 

 advantages of hot walls are well illustrated by 

 their influence in ripening peaches, nectarines, 

 and similar fruits in England, Scotland, and 

 many parts of the north of Europe, where such 



fruits could not be produced in the open air 

 without this aid. 



HOUND. An appellation given to dogs of 

 the chase. See DOG and GREYHOUND. 



HOUNDS'-TONGUE (Cynoglossum). A 

 genus of herbaceous plants, of which only two 

 species grow wild in Great Britain. The cul- 

 tivated foreign species are pretty border plants, 

 succeeding in any common soil, and readily 

 multiplied by division. 



1. Common hound's-tongue (C. offirinale) is 

 found abundant in waste ground and by road- 

 sides. The root is fleshy and tapering. The 

 whole herb of a dull green, downy, and very 

 soft, exhaling when touched a pungent and 

 nauseous scenL When bruised it is affirmed 

 to drive away mice. The stem grows to two 

 feet high, branched, leafy, furrowed, and hairy, 

 bearing terminal panicled clusters of dull 

 crimson flowers. This plant is eaten by goats, 

 but refused by sheep, horses, hogs, and cows. 

 It has a bitter taste, ;unl is esteemed powerfully 

 narcotic and dangerous for internal use. The 

 roots are astringent and sedative; and are used 

 externally and internally in decoction in cases 

 of scrofula. 



2. Green-leaved hound's-tongue (C. sylvati- 

 cum). This is a more rare plant, growing by 

 n ;!-> ides and hedges in shady situations, and 

 is distinguished from the common species in 

 its bright shining green colour, and want of 

 downy softness, besides having scarcely an}' 

 scent. The flowers, which blow in June, are 

 at their first opening reddish, subsequently of 

 a dull blue. (Smith' $ Eng. Flor. vol. i. p. 259 ; 

 Paxton't Rot. Dirt.) 



Four species of this plant are enumerated in 

 the United States. The common hound's-tongue 

 is a foreigner, now frequent in the Middle States, 

 and extending itself throughout the country. It 

 is a biennial, and may be readily known by its 

 disagreeable odour, somewhat resembling that 

 of young mice. It formerly enjoyed some re- 

 putation for medicinal properties. 



The wild comfrey (C. Virginicwn) has a pe- 

 rennial root, and is common in rich woodlands. 

 The root is mucilaginous, and frequently em- 

 ployed, in domestic practice, for complaints of 

 the chest, internally, and externally in poultices 

 for bruises, sprains, &c. 



HOUSELEEK (Sempervivum, from semper 

 vivo, to live forever; the tenacity of life in the 

 houseleek is well known). There are seven 

 species of houseleek mentioned by Miller (but 

 these are only a few of this extensive genus). 

 They all thrive best on dry rocky situations. 

 These interesting plants are worthy a place in 

 every collection. The mountain houseleek is 

 a very hardy perennial, bearing a purple flower 

 in June and July. The houseleek (S. arboreum), 

 which is a native of the Levant, is hardy and 

 handsome, bearing a golden-yellow flower in 

 autumn and even in winter. Cuttings taken 

 off and laid to dry for two or three days, will 

 root very freely. The juice of the common 

 houseleek (S. tertorum), applied either by itself 

 or mixed with cream, gives immediate relief in 

 burns or other external inflammations. (Pax- 

 ton's Bot. Diet.) 



HOVEN. See CATTLB, and SHEEP, DIS- 

 EASES OF. 



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