5 1 8 Of Chimney Fireplaces. 



to the height to which the new back and covings ought 

 to be carried. This will depend not only on the height 

 of the mantle, but also, and mpre especially, on the 

 height of the breast of the chimney, or of that part of 

 the chimney where the breast ends and the upright canal 

 begins. The back and covings must rise a few inches, 5 

 or 6 for instance, higher than this part, otherwise the 

 throat of the chimney will not be properly formed ; but I 

 know of no advantages that would be gained by carry- 

 ing them up still higher. 



I mentioned above, that the space between the walls 

 which form the new back and covings, and the old back 

 and sides of the fireplace, should be filled up; but this 

 must not be understood to apply to the space between 

 the wall of dry bricks, or the tile which closes the passage 

 for the chimney-sweeper, and the old back of the chim- 

 ney ; for that space must be left void, otherwise, though 

 this tile (which at most will not be more than two 

 inches in thickness) were taken away, there would not 

 be room sufficient for him to pass. 



In forming this doorway, the best method of proceed- 

 ing is to place the tile or flat piece of stone destined for 

 closing it in its proper place, and to build round it, or 

 rather by the sides of it, taking care not to bring any 

 mortar near it, in order that it may be easily removed 

 when the doorway is finished. With regard to the rab- 

 bet which should be made in the doorway to receive it 

 and fix it more firmly in its place, this may either be 

 formed at the same time when the doorway is built, or 

 it may be made after it is finished, by attaching to its 

 bottom and sides, with strong mortar, pieces of thin 

 roof tiles. Such as are about half an inch in thickness 

 will be best for this use ; if they are thicker, they will 



