28S THE FORCING GARDEN". 



The sole of two-inch thick tiles, each fifteen 

 inches long, by twelve broad; jointed on cross 

 bricks on edge, or pillarets, to keep them about 

 four inches clear of the surface. The walls of w^ell 

 moulded, or stock bricks, six inches clear of each 

 other, and the height of two bricks placed on edge, 

 covered with inch and half thick tiles, each twelve 

 inches long and ten broad, laid the length to the run 

 of the flue; by which means the covers will not be 

 flush with the sides of the flue, but each edge will 

 be champhercd or bevelled, which makes the flue 

 look very light and neat. The open or void of the 

 flue will thus be (with the height of two bricks on 

 edge, and two joints of lime), ten hy six inches, or 

 thereby. It is clear and detached on all the four 

 sides, except the interruptions of the pillarets; and 

 is the most eflfectual flue of many different sizes I 

 have tried, as said above. 



The joints should be carefully filled with fine 

 lime, in soles, walls and covers; but no plaster 

 should be used, either within or without. It is a 

 gross error to plaster any flue; as, by doing so, the 

 heat is conducted out at the chimney, instead of 

 being let into the house through the pores of the 

 bricks. A few feet, that is, six or eight, next to 

 the furnace, should be of fire-bricks and tiles, in 

 order to withstand the strong heat; and the flue 

 should always extend quite through, to the outside 

 of the wall of the hot-house. The furnace, w^he- 

 ther placed at back, front, or end, should never 

 come within the house. This is a measure of pre- 

 caution very necessary to be taken; as many acci- 



