272 On the Construction of Kite fan 



The farther end of the roaster must be so fixed in 

 the brick-work that no part of the smoke can find its 

 way from the fire-place, B, directly into the canal, D, 

 otherwise it will not pass up by the sides of the roaster 

 to the top of it. At the top of the roaster, at its farther 

 end, an opening must of course be left for the smoke to 

 pass into the descending canal, D. 



As I have already mentioned the necessity of causing 

 the smoke which is used for heating an iron oven or a 

 roaster to descend before it is permitted to pass off into 

 the chimney, I shall insist no farther on that important 

 point in this place. It may, however, be useful to 

 observe that, if the place where a roaster is set is not 

 deep enough to allow of the descending canal, D, and 

 the canal, F, by which the smoke ascends and passes 

 into the chimney, to be situated at the farther end of 

 the roaster, both these canals may, without the smallest 

 inconvenience, be placed on one side of the roaster; 

 indeed, as houses are now built, it will commonly be 

 most convenient to place them on one side, and not at 

 the end of the roaster. When this is done, the smoke 

 must be permitted to pass up behind the farther end of 

 the roaster, as well as by the sides of it. 



By taking away a large flat stone, or a twelve-inch 

 tile, placed edgeways, a passage from A to E may be 

 opened occasionally, in order to clean out the canals, D 

 and F, and remove the soot. These passages may be 

 cleaned out either from above or from below, by means 

 of a brush with a long flexible handle. 



The steam-tube (which is seen in this figure) must 

 open into a separate canal (not expressed in the figure), 

 which must be constructed for the sole purpose of car- 

 rying off the steam into the chimney or into the open 



