118 



protect a peach-wall. The stone coping of this wall 

 projects over it about an inch and a half, with a 

 groove or throating underneath. Coping-boards nine 



inches broad, -^tted to join at their ends by means of 

 plates of iron, are supported on iron brackets built 

 into the wall. The annexed figure, 18, shews one of 

 these brackets, in which a is an iron which is built 

 into the wall, the thickness of a board below the stone 

 coping ; and b, the hole for the iron pin which secures 

 the wooden coping. To these brackets the coping- 

 boards are secured by broad-headed iron pins, passing 

 through corresponding holes (6) in the board and 



Fi:r. IS. 



bracket, a slip of iron, or ''spare-nail," being then in- 

 troduced through an eye in the lower end of the pin. 

 The upper edge of the board is slightly levelled, so as 

 to fit as closely as possible to the under side of the 

 coping of the wall, in order effectually to obstruct the 

 radiation of heat, and the ascent of warm air. From 

 this coping, woollen netting of various kinds, common 

 netting such as fishermen use, bunting, and thin can- 

 vass, have been let down, and tried experimentally, in 

 the course of the last fifteen vears ; and we are ia- 



