CONSTRUCTION OF THE GREEN-HOUSE. 145 



tiles, which should be twelve inches square. Soft bricks and 

 good mortar are the other requisites. 



Building the furnace. The furnace is the first to be at- 

 tended to, which should be at least fifteen or eighteen inches 

 below the level of the flue, in order to have a good draught. 

 The size of the furnace must be thirteen inches wide, in order 

 to give space for taking out the bars, when it is requisite to 

 clean the furnace ; the bars must rest on the two iron sup- 

 porters, underneath which will be the ash-hole, of the same 

 dimensions. An arch of fire-bricks must be turned over the 

 grating, fifteen inches high in the centre. 



There should be a neck of a curvilinear form, from the 

 furnace to the flue, about three feet long, with a regular ascent 

 of one foot, to cause a good draught. 



Position of the flue. The position of the flue should be 

 such as to turn round the front and back of the house, from the 

 north-east to the north-west corner, where the smoke should 

 be carried horizontally from the neck before spoken of. 



Dimensions of the flue. In building the flue, I recom- 

 mend for a foundation, that bricks be laid in mortar, to the 

 width of twenty-one inches from the wall. On this founda- 

 tion, two courses of bricks must be laid on their edges ; one 

 three inches, the other fifteen, from the wall, leaving a space 

 of four inches between each brick, so as to form a pigeon 

 hole under the flue : on these two courses, lay a plank for a 

 foundation, on which lay either brick or tiles, for the bottom 

 of the flue; then proceed with three bricks, on their edges, 

 each side the bottom of the flue, which, when covered with 

 the upper tiles, forms the flue, the inside of which will be 

 twelve inches deep and eight wide. 



AKT. 3. Walk and Stages. 



Adjoining the foundation of the flue, round the front of the 



house, I recommend a walk, two feet wide, to be laid with 



an inclination of half an inch in ten feet, to the south-east 



or south-west corner, to carry off the water, which can be 



13 N 



