72 PRACTICAL FLORICULTURE. 



may be used to a very good purpose. Any mason will be 

 able to build a smoke flue, by having the following instruc- 

 tions. Let the bars of the grate be from 20 to 30 inches in 

 length, making a width of grate from 10 to 15 inches, accord- 

 ing to the size of the house to be heated ; say the smallest 

 size for a surface of glass of 300 feet, the latter for 600. 

 Where the furnace pit can be drained, if there is danger 

 of water standing in winter, it is always best to place the 

 furnace so deep that the furnace bars will be say 3 feet 

 from the top of the flue where it first starts along the 

 house ; at all events, the bars should never be less than one 

 foot below the bottom of the flue. After setting the grate 

 bars in the usual way, by resting them on an iron plate let 

 into the brick-work at front and back, the sides of the fur- 

 nace should be built with fire brick and fire clay, (if at all 

 procurable), to the height of 10 or 15 inches, according to 

 size. From that point an arch is turned over to cover the 

 furnace, the " neck " of the furnace rising at a sharp angle 

 for about 2 feet, until it runs into the flue. The flue should 

 be raised from the ground by means of bricks, either one 

 upon edge or two laid flatwise. This costs perhaps one-third 

 more in building, but it exposes a greater heating surface, 

 besides keeping the flue always dry, and permitting it to 

 " draw " better at all times. The cheapest and simplest form 

 of flue is made as follows : After the bottom is formed, the 

 flue is built up by placing two bricks on edge, the top being 

 covered by a brick laid flat. This may be varied, how- 

 ever, for larger houses, by placing 3 bricks on edge and 

 covering by tiles. The larger the furnace, of course the 

 greater the necessity for a larger flue. A flue had better 

 never exceed 120 feet in length, and this length should be 

 secured by running the flue along one side of the housi , 

 crossing the end, and returning along the other side to 

 the place of beginning, where it connects with the chim- 

 ney. If the flue can have a gradual rise of 1 or 2 feet ID 

 its entire length, so much the better. Whenever it is made 



