9 
Steam Engine. 
come from the lire-place to the boiler. E E is a place 
to contain the ashes j and F is a door to take them out 
at, which must be kept continually shut during the time 
of working. G H is the fire-place : the fresh fuel is put 
in at and gradually comes down as the fuel below 
consumes* The part at H is very hot, being filled with 
the cokes or coals which have ceased to smoke. I is an 
opening or openings, to admit fresh air, and regulate the 
fire. K is a door into the space under the boiler ; which, 
being opened, admits air, and stops the draught of the 
chimney when the operation is Wanted to cease. Figure 
the second is a section of the same fire-place in the 
other direction ; in which M M is the back of the fire- 
place ; L the brick arch on which the fuel lies 5 and E 
the ash-hole. Figure 3 is an outside view of the same 
fire-place, shewing the air-holes 1 1 , and the ash-hole door 
F ; and Figure 4 is a plan of the same, with part of the 
boiler seating, taken in the line Z Z of Figure 1 . The 
dotted lines represent the flues, and the darts point out 
the direction of the flame* The fire is first kindled upon 
the brick arch L, (Fig 1 .) and when well lighted, more 
fuel is gradually added until it is filled up to G ; and 
care is taken to leave proper interstices for the air to pass, 
either among the fuel, or between the fuel and the front 
wall N ; and as much air is admitted at 1 1 as can be 
done without causing the smoke to ascend perpendicularly 
from G, which it will do if too much air is admitted at 1 1. 
The dimensions of this fire-place are shewn by the scale, 
and are properly adjusted for burning about eighty-four 
pounds weight of coals in an hour ; w^here greater or less 
quantities are required to be burnt, the furnaces must be 
enlarged or diminished accordingly ; or, if much greater, 
more furnaces than one must be employed. Figure 
the fifth represents this new fire-place as applied to a 
furnace for melting iron and other metals, and construct- 
Vol. IL B 
