Remarks on the hot Water System. 429 



On Warming, &c. ; but must defer it to some other oppor- 

 tunity, on account of the length of this letter. 



I am, Sir, &c. 

 16. Grove Place, JLisson Grove, Thomas Tredgold. 



January, J 827. 



Note to the two pr-eceding Papers. — The impression upon 

 our mind from Mr. Whale's paper [Gard. Mag., p. 186.) 

 was, that both Mr. Atkinson and Mr. Bacon had made 

 the application at the same time, and that, had Mr. Atkin- 

 son considered himself entitled, he would have laid claim 

 to the discovery. It now appears, from Mr. Barrow's 

 paper, that Mr. Bacon's trials or experiments were not made 

 from so correct a knowledge, or at least so clear an appli- 

 cation, of principles, as those of Mr. Atkinson ; otherwise, we 

 conceive, he would not have thought of heating the water in the 

 reservoir with only one pipe. At the same time, it must be 

 recollected that Mr. Bacon is no more, and therefore we wish 

 to say nothing respecting his merits in this discovery, that 

 we should not say were he now before us. We have heard 

 that Mr. Bacon stated before the Committee for Mechanics, 

 at the house of the Society of Arts, that he took the idea of 

 heating hot-houses by hot water, from having seen, above 18 

 years ago, a leg of mutton boiled in a horse-pail, a feat sometimes 

 performed for a wager at fairs. The breech of a gun-barrel is 

 put in the fire, and the muzzle inserted into the side of the pail, 

 near the bottom : and, a strong fire being kept up, the water 

 in the pail is made to boil, and kept boiling, by its communi- 

 cation with the heated end of the gun-barrel. Mr. Cottam, of 

 Winsley Street, saw this done in a smithy near Manchester. 



It appears from the Dictionnaire Technologique, article 

 Assainissement, that the idea of heating by circulating hot 

 water was realised by M. Bonnemain, a French physician, 

 on or before the year 1777. M. Bonnemain applied the 

 art to the hatching of chickens, and occupied himself in 

 this way as a matter of business, in the neighbourhood of 

 Paris, during the fifteen years which preceded the commence- 

 ment of the French Revolution. In the work referred to, 

 under the articles Assainissement, Incubation, and Chaleur, 

 will be found the details illustrated by figures. M. Bonne- 

 main is said to have applied his mode of heating, with success, 

 to the maintenance of an equal temperature in stoves and 

 green-houses (Chal., p. 377.), and to have recommended its 



