HOT-HOUSE. 135 



hole will not require to be so deep; or where there is only 

 one door in the house, a stock-hole three and a half feet 

 deep will be enough, which should be built like a cellar, 

 to keep out any under water. In all instances pass the 

 first flue to the front of the house, over which have a close 

 table, covered with two inches of sand, and, by keeping it 

 moist, will afford a very congenial heat to young and valu- 

 able plants. Likewise over the furnace have a frame in 

 the same manner, which will be found useful for propagat- 

 ing. Any part of the furnace or flue that is under the 

 floor of the house, should have a vacuity on both sides to 

 let the heat pass upward. 



Furnaces and flues on the above construction are the 

 most simple in arrangement, and the easiest to manage at 

 all times. But where capital, taste, and practical science 

 can be united, a more elegant disposition of heating con- 

 venience can be adopted : an excavation should be made 

 for the flue to pass along under the pathway, which path- 

 way may be a casting of iron, or wooden slats, fancifully 

 put together, and at least six inches above the flue. In 

 building the furnace, place thereon a boiler of cast-iron or 

 copper, about two feet deep, two feet long, and four inches 

 wide, with a zinc or copper lid : having it prepared to re- 

 ceive two pipes, one near the bottom and the other about 

 four inches from the top : these pipes may be from four to 

 six inches in diameter, and are to be taken along under the 

 table in front of the house, in a level position, and, at the 

 end of the house, joined together by a perpendicular pipe, 

 or joint which should have an end about one foot higher 

 than the highest part of the upper pipe. When all is pro- 

 perly fixed, fill the boiler with rain or river water, if possi- 

 ble : the air in the pipes will pass out at the perpendicular 

 end, and, when all are full, put a perforated cover on the 

 end of the pipe. As soon as the water becomes heated, it 

 will arise from the bottom of the boiler, and pass along the 

 upper pipe, and return cool by the under one. Or, in 

 place of the pipe returning again by the front, it can pass 

 all round the house, only there must be a piece of perpen- 

 dicular pipe to allow the air to get out the consumption 

 of water will not be over half a gallon in twenty-four hours. 

 If the pipes require to be higher than the boiler, the boiler 

 cover must be hermetically sealed, and the filling operation 



