to be fee 8. or i afoot higher than the Hole D and the Shutter 
made of Iron, or Wood that will not flirink, that it may flint 
very clofe ; this Dore being made large enough to receive the 
-Cradle with eafe. 
G. The- Grate or Cradle ^ which is narrower below than a- 
bo ve,that the Allies may the more eafily falfand the Air excite 
the Fire ; the bottom being barred as the fldes. 
rL The Border or Ledge of the Cradle 5 that red's upon the 
hedge C. 
1. Four Chaim of Iron faftned to the four corners of the 
Cradle Jot taking of it up, ail d letting of it down. 
Ks T . lie Chain of Iron , to which the other are faftned. 
L. The Pulley o( Iren or Brafs , through which the Chain pah 
•feth. 
M. A Beo \ , on which the end of the Chain is faftned by a 
Bing, the Hoo\ fixed being placed in the fide of the Dare. 
N A Barr of Iron in the Walls, to which the Pulley is faftned. 
The higher the Shaft of the Chimney is , the Fire draws 
the Air the better. And this Invention may be made life of 
in the Pits or Shafts . that are Perpendicular , or any wife incli- 
ning towards it,when there is want of frcfli Air at the bottom 
thereof, or any moleftation by unwholfom Fumes or Vapours. 
A way to brea^eaiily and jpeedily the hardeji 
Rocks., communicated by the fame Perfon , 
as he received it from Monfeur Du Son . 
the Inventor , 
Though the Invention of breaking with eafe, and difpatch, 
hard Rocks, may be ufeful oil fever al occafions, the benefit is 
incomparably great , that may thereby accrue to thofe, who 
have Adits or P adages to cut through hard Bpckj^ for making 
paflfage for Water to run out by, in Mines of Lead, Tin , or any 
other whatfoeverghefe Adits appearing to be the fared:, chea- 
'peft, and mod advantageous way imaginable, for draining of 
Ihe fame. That 
