T n I 



T H O 



air of the stove, pronioterl by fire, 8cc. points 

 out on the scale the proper degree of heat re- 

 quired, having the name of some remarkal)le 

 exotic, such as the anana, or pine-apple, written 

 on the scale as a standard mark of the requisite 

 temperature of heat, so as when the internal 

 heat of the stove raises the spirit to that mark, or 

 Avithin five degrees over or under, is the proper 

 temperature for the growth of the ananas, and 

 all other tender plants from the hottest parts of 

 the world ; so that the fires requisite for the 

 stove in winter, are to be made stronger or 

 weaker accordingly. 



They are more particularly useful in winter, 

 during the time the fires are made in the flues 

 for warmin:^; the air internally ; one being generally 

 hung up toward the centre of the stove, so as the 

 warmth may operate moderately and equally on 

 every side, and discover the real temperature of 

 the general internal heat, which should be sup- 

 ported always nearly equal by the aid of bark 

 hot-beds and real fire, sufficient to raise the spirit 

 or other fluid in the tube to the mark ananas, 

 or but a little over or under it. 



They should not only be suspended nearly to- 

 wards the centre of the stove, but also out of the 

 sun, that the glass tube and ball containing the 

 spirit or other fluid may be shaded as much as 

 possible ; and also at some medium distance 

 from the fire-place and flues, so as neither the 

 direct rays of the sun, or heat of the fire, darting 

 immediately on the tube and bail, may affect the 

 operation of the inclosed fluid, and cause it to 

 mount higher than would be effected by the real 

 general warmth of the air of the stove, and 

 thereby lead into an error, in supposing the in- 

 ternal heat to be much stronger than it really is, 

 when probably it is not strong enough. See 

 Ananas. 



THICKETS, a sort of close plantations of trees 

 and shrubs, in pleasure-grounds, parks, &c. 

 They are designed for different purposes, as some- 

 times to repel the force of tempestuous and cold 

 cutting winds, either from the habitation, or 

 some particular part of the garden ; or to form 

 places of shade or retirement in summer, having 

 spaces for walks, recesses, &c. under the um- 

 brage of the trees, and occasionally to conceal 

 from view any unsightly or disagreeable object, 

 and also sometimes to form a screen or blind ar- 

 ranged towards some outward boundary. 



On some occasions, they are introduced in the 

 internal parts of large pleasure-grounds, and 

 parks, in contrast to the more open and airy 

 plantations, in which to have shady wood- 

 walks winding variously through them, also 

 to form recesses, by environing particular spaces. 



rendering them retired, shady, and sheltered, by 

 the surrounding trees and shrubs composing the 

 thickets : close thickets of hardy trees and 

 shrubs are sometimes also disposed in detached 

 clumps in capacious open situations, to effect a 

 diversified ornamental variety, the clumps being 

 distantly stationed so as not to obstruct the view 

 of any desirable object. 



Thev are sometimes planted wholly of the 

 large tree kinds, five or six to eight or ten feet 

 asunder, some in regular lines like a close grove, 

 or more generally in a sort of promiscuous plant- 

 ing, but with some degree of order in the di- 

 stances : they are also often composed of various 

 trees and shrubs together to efi'eet a more full, 

 close growth below and above, and to display a 

 greater diversity in the plantation, by disposing 

 the various shrubs properly between the larger 

 trees, in some order of gradation, the lowest to- 

 wards the front, and the taller growths back- 

 ward, so as to form a sort of close underwood 

 thicket below, while the trees run up and form 

 a thickety growth above : and sometimes thev 

 are formed wholly of shrubs of different sorts and 

 degrees of growth, from the lowest placed for- 

 ward to the tallest behind. 



They are sometimes formed wholly of parti- 

 cular sorts of trees disposed separately in distinct 

 plantations, as of elm, ash, beech, poplar, alder, 

 willow, &c. 



The planting of thicket plantations should be 

 effected with young trees of from four, five or six, 

 to eight or ten feet growth, and the shrub kinds 

 proportionally ; in all of which the planting may 

 be performed in the common seasons of autumn, 

 winter and spring. 



In the culture of thicket plantations, little is 

 required but that of keeping them clear from 

 large overbearing weeds, while the trees and 

 shrubs are in young small growth. 



THISTLE, GLOBE. See Echinops. 



THISTLE, MELON. See Cactus. 



THISTLE, TORCH. See Cactus. 



THORN APPLE. See Datura. 



THORN, BOX. See Lycium. 



THORN, CHRIST'S. See Rhamnus. 



THORN, COCKSPUR. See Crat^gus. 



THORN, EGYPTIAN. See Acacia. 



THORN, EVERGREEN. See Me.spilus. 



THORN, GLASTONBURY. See Crat^- 



GUS. 



THORN, GOAT'S. See Tragacantha. 

 THORN, HAW. See Crataegus. 

 THORN, LILY. See Catesb^a. 

 THORN, PURGING. See Rhamnus. 

 THORN, WHITE. See Crat^gus. 

 THORNY TREFOIL. See Fagonia. 

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