METHODS OF FORCING. 



247 



should be continued every evening, and kept up 

 till nine or ten o'clock, and left in such a manner, 

 that it will continue to warm the house durin^ 

 the night; but this part must greatly depend 

 on the nature of the weather, and the season of 

 the year ; and where there is no bark, or other 

 hotbed ? the heat of the flues or pipes should be 

 revived in the morning, and continued mode- 

 rately throughout the day ; and where there 

 is a bark bed, this will also be necessary on 

 cold mornings, and likewise all day, in severe 

 weather; as the season advances, the thermo- 

 meter should be constantly watched, and the 

 artificial heat be increased by fire, or decreased 

 by air according to the power of the sun, thereby 

 keeping a moderate kind heat, which is not 

 only desirable, but absolutely required for tree 

 fruits; the standard for artificial heat being 

 sixty degrees, and ought not to vary after the 

 fruit is set, more than four or five degrees under 

 or over 



The vinery is altogether different, the house 

 may be kept at a much higher temperature, 

 particularly when they are required to be 



