552 THE GREEN-HOUSE [jAN. 



centre of the house), at tlie times of regulation, sup- 

 pose seven or eight in the morning, and eight or 

 nine in the evening ; working as steadily as possi- 

 ble, and being careful to guard against sudden 

 changes in the weather. 



Of the admissio7i of Air to the Green- Hous^. 



Air must be introduced every day, if the weather 

 be not over severe ; but even in pretty Iiard frost, 

 in the time of sunshine, and for two or three liours 

 about the middle of temperate days, the house 

 should be aired by the sashes, or by the ventilators, 

 as directed in the Forcing Garden for January and 

 Februar}^ ; which see. In continued dull weather, 

 pretty strong fires may be made in the morning, in 

 order to dry oif damp, and to allow a freer circula- 

 tion for a few hours, than usuaL 



This treatment should be repeated occasionally, 

 and may be varied according to circumstances; but 

 it is necessary to the preservation of many plants at 

 this season, and so ought to be practised to a cer- 

 tain extent. At suvch times, and in better weather, 

 air should be admitted so freely, as to keep the 

 mercury in the thermometer down to 40° ; for if 

 frost he just excluded for this short period, none 

 of the plants can be hurt. 



Of Wateringi 



Water must be given with great caution at this 



season. Few of the plants will require much, and 



some hardly any ; but all must be attended to, and 



have water according to their wants. Those placed 



