51 STATISTICAL SURVEY 



a fod of fixteen feet, as it muA lap over the vertex, 

 and come down to the outfide face of the wall. They 

 are rolled upon a (lick, and carried up the ladder by 

 two men, who perform their work very dexteroufly. 

 An aftive man can cut from thirty to forty fods of the 

 above dimenfions in a day, and the general price is a 

 penny a fod, but he mufl aflifl to lay them on the roof, 

 and fit them there, which requires fome degree of in- 

 genuity. Under is a fltetch of the fcraw-cutter. 



c . 



The crofs piece a, 2 feet, 



Brace, b, i foot, 8 inches, 



Length from c t to d t 4 feet 6 Inches, 



from d, to s, 7 inches, 



f rom f t to g, 10 inches, and about the 



fame in breadth. The rife, or upfet, from </, tog, is 

 to be con fide r ably more than that of the bed of a 

 fpade. 



SECT. 



