of heating by Hot Water. 



25 



on which it is constructed is all that v.e wish to point out, as it 

 can be made of any din:iensions, and work with equal facility. A 

 cistern [Jig 1,) is made for the purpose of holding water: this 

 cistern is divided in the centre by a strip of board or plank, (6) 



with the exception of an open 

 2 space at one end, as seen in the 



plan: at the other end the hot 

 water enters, though one of the 

 pipes, (« a) which may be made 

 of copper or iron, and circulat- 

 ing round the cistern by means 

 of the open space just men- 

 tioned, returns to the boiler 

 through the other. The water 

 enters and leaves the cistern on a 

 level, but the return pipe, just 

 outside, drops down by means of 

 an elbow, and the water returns 

 with the same facility as from a common reservoir. The depth 

 of water is about five inches, as will be seen in the section, 

 (A^--2.) . . , 



Mr. Sweetser's pit measures about sixteen feet in length, and 

 three in breadth. The cistern takes up but part of this, as seen 

 in the plans, and is about twenty inches wide and six inches high. 

 Across the pit, about four inches from the surface of the water 

 in the cistern, joists or plank are laid, to support a covering of 

 bricks and stones, on which the soil, consisting of decayed leaves 

 and light mould, is placed, for plunging in the pots of plants. 



When the fire is applied beneath the boiler, the water circu- 

 lates freely, and that in the cistern soon becomes heated; the 

 warm air rises tlirough the bricks, which are laid without mortar, 

 and stones, heating them in its course, and communicates with 

 the soil: the evaporation is just sufficient to keep the soil in a 

 moist state, highly conducive to the vigor and health of the plants. 

 Fires are not required during the day, as the great body of water 

 will retain sufficient warmth to keep the heat of the soil above 

 from declining. The bricks and stones also retain their warmth 

 for a great length of time after the fire is out. 



This pit has been in operation several weeks, and continues 

 to affiDrd the greatest satisfaction. There is always a genial 

 warmth in the soil, and the pipes communicating from the boiler 

 to the cistern, together with the flue, keep the air of the house 

 at as high a temperature as is required. This is an important 

 thing in the construction of the pit; as the same pipes in all ca- 

 ses, no matter how large the dimensions of the water cistern, that 

 warm the house, may be conducted into it: and, if required, can 

 leave it, and still continue further round the house before they 



VOL. III. NO. I. 4 



