Retrospective Criticism. 



63 



Bailey 

 should 



Our correspondent is quite correct ; hot water will onh' 

 des,cend below the level of the vessel in which it is heated, 

 under such arrangements as those adopted by the Marquis de' 

 Chabannes (p. ,30.), or as exemplified by Messrs. Bailey in a 

 model {fig. 45.) now at work on their premises, 272. Holborn. 

 In this model, the water, after being heated in the boiler {a), 

 rises to the covered reservoir several feet above it {b), from' 

 whence it descends, on the principle of pressure, by the pipe 



(c c), and returns to the 

 ^'^ boiler by pipes consider- 



ably below its level {dd), 

 which may be bent in 

 any direction. This ap- 

 plication may be useful 

 both in the case of dwel- 

 ling-houses and hot- 

 I houses, and it has already 

 ^been applied by Messrs. 

 in the case of a green-house, where it was necessary that the pipes 

 descend below the pathway (as at e). — Cond. 



^ Heating hy hot Water at Sundridge Park and Russet Ptace. — Dear Sir 

 Since I saw you I have seen Mr. Scott, who states that his apparatus in the 

 conservatory at Sundridge Park, was fixed under the direction of the Marquis 

 de Chabannes, in 1816 and 18 17, and that healtered itin 1821, having, in the 

 first instance, had the boiler formed of small tubes, and the conducting 

 pipes of lead, neither of which answered. The material now employed is 

 copper, and the boiler is in the form usually employed for generating steam. 

 Mr. Scott farther informs me, that he saw, a year or two before he em- 

 ployed the Marquis de Chabannes at Sundridge, the house of Messrs. 

 Cooper and Balls, in Drury Lane, heated by warm water ; and that the Mar- 

 quis also warmed the house No. 1. Russel Place, by water, in 1815. He 

 has also been informed that Messrs. Boulton and Watt, of Scho, Birming- 

 ham, practised this mode of heating upwards of twenty [fifty, see p. SO.] years 

 ago. The mode in which the conservatory, and the hot-houses in the 

 kitchen-garden, at Sundridge Park are heated, well deserves your atten- 

 tion. I assure you, the principle is very ingenious, and the end completely 

 attained. I am, dear Sir, &c., — George Cottam. Manufactory, Winsley 

 Street, Oxford Street, Feb. 19. 1828.| 



In a letter recently received from Mr. Thompson, the kitchen-gardener 

 at Sundridge Park, he informs us that Chabannes's apparatus answers most 

 completely; and that,bythepower of throwing the hot water at pleasure into 

 one or several of the cisterns containing air-tubes, he can, in the coldest 

 weather, raise the air of the house to 100° in a few minutes. What these 

 reservoirs containing air-tubes are, may be ascertained by referring to the 

 review of the Marquis de Chabannes's pamphlet, (p. 29.fig.21. g g g) 

 We agree with Mr. Cottam, who has applied the hot water system under 

 various modifications, that the apparatus at Sundridge ought to be under- 

 stood by every one who has occasion to circulate hot water under any other 

 than ordinary circumstances. — Cond. 



Thymelets, not ThymelecB. — A botanist, whom we consider the very first 

 authority in accentuation, as in every thing else connected with the subject, 

 informs us that our correspondent N. T. (Vol. III. p. 482.) is wrong as to this 

 word, and that the true accentuation is Thymeleae, to which we shall 

 adhere in future. — Cond. 



The Scotch Elm, which you recommend, I have found, on light sandy 

 soils, very subject to breaking in the bark. [?j — X.Y.Z. 



