BOOK I.] INTRODUCTION. 7 



dy of foil, for the fupport of vegetable life, 

 than otherwife might be required. 



In the cultivation of exotic plants and 

 fruits in hot-houfes, regard muft be had 

 to the climate of their nativity j and the 

 beft endeavours mould be ufed to v imitate 

 it in the hot-houfe ; introducing the na- 

 tural changes of the feafons with equal care. 



This, however, is done with confiderable 

 difficulty, as may be conceived, by confi- 

 dering the difference of latitude, and the 

 variation of the fun's altitude throughout 

 the feafon, which is greater as we approach 

 the pole. 



Hence the difference of trouble attend- 

 ing early and late forcing. And hence, 

 alfo, the difference of injury done the 

 plants in the operation 3 and, that they 

 may fuftain the lefs, the neceflity of a more 

 moderate treatment in the one than the 

 other. The one is Jlr'ming, the other ftri- 

 ving hard againft the flream. 



Sudden checks of any kind are to be 

 avoided, particularly while the bloom or 

 fruit is in a tender and infant ftate, other- 

 wife difappointments may be apprehended. 

 This is to be more particularly attended 

 A 4 to 



