22 



BIGGLE GARDEN BOOK 



with flat Stones. Six-inch drain tiles make good 

 flues. The furnace can be made of stone or brick. It 

 should be two feet wide, two feet high and four feet 

 long. Old grate-bars, or a section of an old boiler, 

 make a fine top for the furnace. Fire beds vary in 

 length from fifty to 200 feet, but seventy-five to 100 

 feet will prove most satisfactory. To insure a good 

 draft the flues must have a rise of three or four 

 feet to the 100 feet of length. For this reason it is 

 better to make the bed on a gentle south slope. Start 

 the bed eight or ten feet from the furnace. The 

 earth on the flues next to the furnace should be at 

 least three feet deep, tapering down to four or five 

 inches at the upper end. It is best to have the bed 

 extend east and west, and the flue on the south side 

 should be within six inches of the edge of the bed. 

 That on the north side can be a foot or more from 

 the edge. At the fire-box the top of the flues should 

 be on a level with the top of the furnace, and both 

 flues should open into chimneys at the upper end. 

 To save fuel the furnace should have a door. 



Greenhouses. — The construction and operation 

 of greenhouses heated by the hot-water system, is 



build greenhouses unless 

 they are operating on a 

 VENTILATION MUST BE CARE- ygj-y largc scalc, iu which 



TTTTT TV DC-/~TTT ATTP* nO flT ACC _ - . 



hardly a subject within 

 the scope of this little 

 book; those who are in- 

 terested in the matter 

 need a special volume — 

 such as Prof. Bailey's, 

 The Forcing Book. Few 

 gardeners can afford to 



FULLY REGULATED, OR GLASS 

 REMOVED ON WARM DAYS 



case they will find it 



