426 Atkinson's Experiments on heating by hot Water. 



were executed under Mr. Atkinson's direction. I bad an 

 opportunity of seeing what Mr. Bacon had done, and also 

 had his model, which went to the extent of his invention ; 

 I have tried it on my own premises, and am quite convinced, 

 as far as his invention went, it never could have been use- 

 fully applied. After the hot water had been brought into use 

 at Mr. Bacon's, the same plan was adopted in a pine pit, 

 about 100 ft. long, at Lord Carnarvon's. In 1826, Mr. Atkin- 

 son adopted it in a conservatory 60 ft. long, 20 ft. wide, and 

 20 ft. high. The pipes are placed under the paving of the 

 footpath, and the heated air let out by gratings. In this house 

 the water has to run 80 ft. from the boiler to the reservoir, 

 and it completely answered in giving out sufficient heat during 

 the coldest nights of last winter, and the fire was never at- 

 tended to after ten o'clock in the evenings ; and, in the 

 severest frost, the water did not lose more than 5° of heat * 

 during the night. When there is a great extent of con- 

 nected glass, as at Messrs. Loddiges', with a proper person to 

 attend the fire, it is probable that steam may be a more con- 

 venient way of heating : but for private gardens, or where the 

 houses are not extensive or connected, hot water has great 

 advantages over steam ; as, from the simplicity of the con- 

 struction, it is considerably cheaper in the erection ; it is not 

 liable to get out of repair ; and there is no risk of bursting the 

 boiler or pipes, as the boiler will answer with a simple wooden 

 cover, and no valves are required. No further attention is 

 necessary than for a common flue fireplace ; and, from the 

 length of time the water is in cooling when once heated, the 

 fire does not require attending enuring the night. It is very 

 convenient for pine pits, from the pipes taking up less room 

 than a flue, and would answer well for cucumber and melon 

 pits, where dung is scarce. In narrow houses there have 

 only been two pipes used, about 4 in. diameter, one to carry 

 the hot water from the top of the boiler to the end of the 

 house, and another under it to bring the water, on cooling, 

 back to the bottom of the boiler. Where the houses have 

 been wide, it has been considered necessary to get a greater 

 surface of pipe heated ; and two pipes have been used, to go 



* Mr. Barrow, we think, is in error here, for it must require a very large 

 mass of water to keep such a house warm all night with a loss of only 5° 

 of its temperature; one pound of coal would raise the temperature of half 

 a ton of water 5° (Rumford's Essays, essay x. p. 12.), and the water could 

 give out no more heat in cooling than it had acquired from the fuel ; now 

 we all know how small an effect one pound of coal would have in pre- 

 serving the temperature of a hot-house all night. — Cond. 



