aO iNTRdDUCTlON", 



his frames to nearly the fame degree as I do, to- 

 gether with a fufficiency of air and moifture, he 

 may rely upon being fuccefsful. 



I do not mean, that the heat fhould be kept to 

 the very fame degree, on every identical day of every 

 year ; for that would be impoffible, unlefs every day 

 in every year were to be of the fame degree of heat : 

 But as that is not in natural vegetation, neither can 

 it be in artificial vegetation j for forcing vegetation 

 is only affifting the climate, where the climate falls 

 fliort In its produ6:ions. 



The following regifler for one day, of the tempera- 

 ture of the open air, and of that of the cucumber 

 frame, may ferve to illullrate the foregoing para- 

 graph. 



Tue/day, February 21/ly 1792* 



If the regifter of this day be compared with that 

 of the fame day of the fame month of the fucceeding 

 year, 1793, ^ difference in the degrees of heat will 

 be feen j and fo it will happen, in a lefs or greater 



degree, 



