( 48 ) 
to drive in a Stream of frefh Air, to fpread uniformly 
all over the Houfe, by coming in at the middle of 
the Cieling. 
The Uies of this Machine for fick Rooms, for 
Prifons, for warming, cooling, or perfuming any 
Chambers at a diftance, were fpoken of in the Ex- 
planation of the Model I lliew’d the Society. The 
Machine may alio ferve in a Man of War, to take 
away the foul Air between Decks, occafion’d by the 
Number of Men in the Ship, and to give them frelh 
Air in a few Minutes. In every Part of the VefTel 
every foul Hole may be render’d wholefome, and 
even the Stench and foul Air from the Surface of 
the Bulge-Water may be carried of. In regard to 
Mines, the Machine mud prove of excellent Ufe ; 
for as the Damps (either fulminating, which taking 
Fire, deftroy the Men and ruin the Works, or ar- 
fenical, which kill by their poifonous Nature) are 
fome (pacifically lighter, and fome fpecifically heavier 
than common Air, this centrifugal Wheel can in a 
little Time drive down Air through wooden Trunks 
(or Launders) of feven Inches bore, in fuch Quan- 
tities into the deepeft Mines, as to caufe all the light 
Damp to come out at the Top of the Pit ; or, by 
only altering two Sliders, luck away all the heavy 
poifonous Damp, whilft wholefome Air goes down 
from above Ground into the Pit, fo as to fill all 
the fubterraneous Caverns with frelh and wholefome 
Air. 
Likewife a great many of the Difficulties which 
attend the carrying on fubterraneous Palfages for the 
Conveyance of Water from Mines (call’d Soughs, 
Adits, or Drifts) may be remov’d by the Help of this 
Wheel ; 
