INTRODUCTION. 267 



mate as it were by stealth ; bringing on, as in na- 

 ture, first spring, and then' summer ; making artifi- 

 cial dews and showers, to refresh the foliage and 

 nourish the root ; admitting air freely, unless of an 

 impure kind; and ventilating the hot-house fre- 

 quently, to purify it of noxious damps, which are to 

 #11 fruits pernicious, especially as they approach to 

 maturity. 



The plants being forced out of their natural incli- 

 nations in a great measure, do not perspire so copi- 

 ously, nor imbibe nutritive matter from the atmos- 

 phere, so abundantly as if they did grow in the open 

 air. Hence it is necessary to compose for them a 

 soil more rich and deep than might otherwise be re- 

 quired, which must be kept in good heart, by the ad- 

 dition of fresh compost, and by the application of fit 

 manures, from time to time, according to necessity. 



In the culture of plants in an artificial climate, 

 regard ought to be had to that of their nativity, 

 which should, as nearly as possible, be imitated in 

 the hot-house ; introducing the natural changes of 

 the seasons with equal care. In our variable cli- 

 mate, however, this is done with considerable diffi- 

 culty, and only by a strict attention to the state of 

 the weather ; which may be conceived by consider- 

 ing the difference of latitude, and the variation of 

 the altitude of the sun throughout the year ; which 

 variation is greater the nearer we approach to the 

 pole. 



Hence, in the forcing of fruits in succession, the 

 difference of trouble attendant on early and on late 

 forcing. Also, the, difference of injury done the 



