148 GREENHOUSES 



To guard against warping of the side and 

 end boards of wood benches, angle irons 

 may be used in the corners and along the 

 sides, and fastened by screws or small bolts. 

 Brick piers may be used in place of the 

 wooden legs. The wooden legs, however, 

 will usually outlast the bottom boards and 

 cross-beams. 



Fig. 85. A type of iron frame bench 



Iron Frame Benches. In the majority of 

 iron frame benches, i-inch wrought-iron 

 pipe is used. It is rarely threaded but is tied 

 together with split malleable iron castings 

 by the use of bolts and set screws. The 

 sides and bottom may be made of wood, iron, 

 slate, tile or even of cement slabs. All are 



