Mr, Watkins on cmJlniMlng a Green- Hovfe, 171 



makes its way out of the pipes. It would be proper 

 neverthelefs, to make arrangements in conilrufting the houfe 

 for ufmg a ftove, in cafe a long fucceffion of cold cloudy days 

 by obfcuring the fun, fliouid reduce the heat in the houfe, 

 below that degree of temperature neceffary for preferving 

 the plants, which is a cafe that will feldom happen, as one 

 clear day will warm the houfe fufficiently to admit its being 

 fhut up for feveral days. 



Plants in a houfe of this kind require lefs water, and do 

 not fuffer for the want of atmofpheric air. It is probable, as 

 the earth is charged with electric fluids, and as vegetable 

 fubftances are known conductors of it, that the bark by its 

 fermentation, not only generates heat, but ferves as a mean 

 to produce out of the earth, an atmofphere for the plants, 

 fufficient with fuch atmofpheric air as will find admiffion, to 

 fupply the quantity exhaufled by the daily rarefadion 

 occafioned by the fun's heat. 



A green houfe has been ufed upon this conflruclion in 

 this State, without having had the leail occafion of being 

 heated by fire. The plants in the fpring were remarkably 

 thrifty ; tropical fruit ripened in it during the winter, and 

 young fruit formed on the trees. It required no other 

 care, than now and then watering the plants, and fhutting the 

 windows as foon as the fun left them. 



