CULTTJKE OF THE EOSE. 



131 



not stand the extremes of temperature between the out- 

 side and inside; but as a hollow wall is an expensive 

 matter, I would recommend to those with whom economy 

 is an object to construct the walls thus: Get strong 

 locust, chestnut, or cedar posts, of length sufficient to 

 allow them to set 3 feet in the ground ; place these 6 feet 

 apart ; outside of these nail hemlock or other rough 

 boards ; against this tack a layer of asphalt or tarred 

 paper, and then against the paper nail the weather- 

 boarding, finishing at the top with a hollowed-out timber, 



BoSHcfofRfM 



Fig. 44. END SECTION OF ROSE-HOUSE. 



6 or 8 inches wide, for a gutter. A green-house of this 

 kind, heating apparatus, and all complete, will cost at 

 present prices from $20 to $25 per running foot; with 

 hollow brick walls, it would cost about $30 per running 

 foot. The use of tarred paper for green-house walls is 

 only a recent one ; formerly we used to fill in with brick, 

 or use double boarding, leaving a space of two or three 

 inches, which was filled in with charcoal, sawdust, or some 

 other non-conducting material ; but the tarred paper is by 

 far the cheaper and better. The rose-house we erected 

 last year contains about 5,000 plants, grown in 10 and 12- 

 inch pots, occupying about a square foot of space for each 



