^76 Mr Hulls’’ Description of' a New-invented Machine , 
and to take up too much room in a vessel laden with goods, pro- 
visions, &c. 2. If this machine is put in a separate vessel, this 
vessel may lie at any port, &c. to be ready on all occasions, 
3. A vessel of a small burthen will be sufficient to carry the ma- 
chine to take out a large one. 4. A vessel will serve for this 
purpose for many years, after she is thrown off, and not safe to 
be taken far abroad. 
u The Explanation of the Machine. (See Plate VIII. Fig. 2.) 
“ Represents the chimney coming from the furnace* 
u B, The tow-boat 
“ C C, Two pieces of timber framed together, to carry the 
machine. 
u D a, D and D h , are three wheels on one axis to receive the 
ropes, M F b and F a. 
66 Ha and II b are two wheels on the same axis with the 
Ians //////, and move alternately in such a manner, that 
when the wheels Da , D and D b move backward or forward, 
they keep the fans I III I I'm a direct motion. 
66 F h is a rope going from II b to D that when the wheels 
D a, D and D h move forward, moves the wheel II h forwards, 
which brings the fans forward with it. 
“Fa is a rope going from the wheel H a to the wheel D a, 
that when the wheels D a, D and D b move forward, the wheel 
H a draws the rope F 9 and raises the weight G, at the same 
time as the wheel H b brings the fans forward. 
“ When the weight G is so raised, while the wheels D a,D and 
D b are moving backward, the rope Fa gives way, and the 
power of the weight G brings the wheel II a forward, and the 
fans with it, so that the fans always keep going forward, notwith- 
standing the wheels Da 9 D and D b move backwards and for- 
wards, as the piston moves up and down in the cylinder. 
“ L Z, are teeth for a catch to drop in from the axis, and are 
so contrived, that they catch in an alternate manner, to cause 
the fans to move always forward, for the wheel H a by the 
power of the weight G , is performing his office, while the other 
wheel H b goes back, in order to fetch another stroke. 
“ Note . — The weight G must contain but half the weight of 
pillar of air pressing on the piston, because the weight G is 
