By Thomas Andrew Knight, Esq. 135 



tare, to be scarcely supportable : and every gardener knows, 

 how quickly the leaves of his plants are injured by the com- 

 bined action of heat and moisture. 



The succulent shoots of trees, however, always appear to 

 grow most rapidly, in a damp heat, during the night ; but it 

 is rather elongation than growth, which then takes place. 

 The spaces between the bases of the leaves become longer, 

 but no new organs are added ; and the tree, under such cir- 

 cumstances, may with much more reason be said to be 

 drawn, than to grow ; for the same quantity only of material 

 is extended to a greater length, as in the elongation of a wire. 



Another ill effect of high temperature during the night 

 is, that it exhausts the excitability of the tree much more 

 rapidly than it promotes the growth, or accelerates the ma- 

 turity of the fruit ; which is in consequence ill supplied with 

 nutriment, at the period of its ripening, when most nutriment 

 is probably wanted. The Muscat of Alexandria, and other 

 late grapes, are, owing to this cause, often seen to wither 

 upon the branch in a very imperfect state of maturity ; and 

 the want of richness and flavour in other forced fruits is, I 

 am very confident, often attributable to the same cause. 

 There are few peach houses, or indeed forcing houses of any 

 kind, in this country, in which the temperature does not 

 exceed, during the night, in the months of April and May, 

 very greatly that of the warmest valley in Jamaica in the 

 hottest period of the year : and there are probably as few 

 forcing houses in which the trees are not more strongly 

 stimulated by the close and damp air of the night, than by 

 the temperature of the dry air of the noon of the following 



