Of Chimney Fireplaces. 523 



alterations to be made for the improvement of their 

 fireplaces. 



Directions for laying out the Work. 



If there be a grate in the chimney which is to be 

 altered, it will always be best to take it away ; and when 

 this is done, the .rubbish must be removed, and the 

 hearth swept perfectly clean. 



Suppose the annexed figure (Plate VIII., Fig. i) to 

 represent the ground plan of such a fireplace ; A B 

 being the opening of it in front, A C and B D the two 

 sides or covings, and C D the back. 



Figure 2 shows the elevation of this fireplace. 



First, draw a straight line, with chalk or with a lead- 

 pencil, upon the hearth, from one jamb to the other, 

 even with the front of the jambs. The dotted line A 

 B (Plate IX., Fig. 3) may represent this line. 



From the middle C of this line (A B) another line 

 c d is to be drawn perpendicular to it, across the hearth, 

 to the middle d of the back of the chimney. 



A person must now stand upright in the chimney, 

 with his back to the back of the chimney, and hold a 

 plumb-line to the middle of the upper part of the breast 

 of the chimney (Plate X., Fig. 5, d\ or where the canal 

 of the chimney begins to rise perpendicularly ; taking 

 care to place the line above in such a manner that the 

 plumb may fall on the line c d^ drawn on the hearth from 

 the middle of the opening of the chimney in front to 

 the middle of the back, and an assistant must mark the 

 precise place e, on that line where the plumb falls. 



This being done, and the person in the chimney hav- 

 ing quitted his station, 4 inches are to be set off on 

 the line c d, from e towards d ; and the point f, where 



