232 On curvilinear Iron Roofed Hot-houses. 



day, in a hot-house with a curvilinear roof such as mine, if 

 the glass were of good quality. I am not prepared posi- 

 tively to say, whether such apprehensions are well or ill 

 founded : but I have thought it* best to be provided with a 

 net, such as those usually employed to protect fruit trees, of 

 proper form to cover my house, if necessary, and I am satis- 

 fied that I could have used it with advantage, if I had pos- 

 sessed it, in some very hot days in the beginning of June. 



The ends of my house are of brickwork ; but I think the 

 end opposite the door, ought to contain a window of about 

 two feet square, to permit a free passage of air through, upon 

 the door being opened in very hot weather : my own house is, 

 however, without one. 



In conclusion I wish to observe, that a curvilinear iron 

 roof, may be erected at much less expense than one of wood : 

 two shillings and sixpence a foot being, I conceive, a fully 

 remunerating price to the builder of such a house as mine, 

 the glass being white, and of the quality called best seconds. 

 Green glass might be afforded on much lower terms, but I 

 do not recommend it, being confident that in our climate, 

 Pine Apple plants suffer a hundred days by want of light, for 

 one in which, with proper care, they sustain injury by excess 

 of it. 



I remain, my dear Sir, 



yours very truly, 



Thomas Andrew Knight. 



Downton, 

 September 18, 1822. 



