226 



REVIEWS. 



Art. I. Transactions of 'the Horticultural Society of London. Second Series. 

 Vol. I. Part III. 4to. London, Hatchard. 



28. Journal of Meteorological Observations for 1829. By Mr. W. B. Booth, A.L, S. 



Twenty-six pages of figures, and a plate of diagrams. 



29. Description of various Modes of heating by Steam for Horticultural Purposes. 

 By Mr. Henry Stothert, Civil Engineer, Bath. Read Feb. 21. 1832. 



One of the most economical modes of applying steam to the heating of 

 hot-houses is, to apply it to a bed or mass of loose stones. This mode 

 appears to have been first adopted by Mr. Hay of Edinburgh, in 1807 (V. 443., 

 and VIII. 330.) ; and has been subsequently applied, by the same eminent 

 garden architect, to a number of pine and melon pits in different parts of 

 Scotland. It has also been adopted in England, and on a very extensive 

 scale, in connection with heating pipes and cisterns of water, at the nursery 

 of Miller and Co. at Bristol. Nothing can be more simple than this mode of 

 applying steam. The bed of stones to be heated may be about the usual 

 thickness of a bed of tan or dung ; the stones may be from 3 in. to 6 in. in. 

 diameter, hard round pebbles being preferred, as less liable to crumble by 

 moisture, and having larger vacuities between. The pipe for the steam is 

 introduced at one end of the bottom of this bed, and is continued to the 

 opposite end. It is uniformly pierced with holes along the two sides, so as 

 to admit of the equal distribution of the steam through the mass of stones. 

 The steam-pipe may be of any dimension, it being found that the only differ- 

 ence between a large pipe and a small one is, that the steam proceeds from 

 the latter with greater rapidity. The steam only requires to be introduced 

 once in twenty-four hours in the most severe weather; and, in mild weather, 

 once in two or three days is found sufficient. After the steam is turned on, 

 it is kept in that state till it has ceased to condense among the stones, and, 

 consequently, has heated them to its own temperature. This is known by 

 the steam escaping, either through the soil over the stones, or through the 

 sides of the pit ; or, when a mass of stones is enclosed in a case of masonry, 

 as in the stone flues of the Bristol Nursery, the point of saturation is known 

 by the safety-valve of the boiler being raised. When we consider the small- 

 sized pipes that may be used for conveying and delivering steam by this mode 

 of its application, there can be no doubt that it is the cheapest mode of heat- 

 ing on a large scale known ; and when we revert to the circumstance of its 

 never requiring to be applied oftener than once in the twenty-four hours, and 

 reflect that this renders all night-work unnecessary, the superiority of the plan 

 does not admit of a doubt. In VIII. 330., there is a copious account, illus- 

 trated by engravings, of the application of this mode of heating to certain pine 

 and melon pits in Scotland, taken from the Memoirs of the Caledonian Horti- 

 cultural Society ; but the description is so encumbered with words, and the 

 engravings with letters, that the simplicity of the plan is rendered, at first sight, 

 23 so intricate by them,as,no doubt, 



to deter many from adopting it. 

 Those, however, who wish to 

 know all that has been said on 

 the subject, will revert to that 

 article, as well as peruse the 

 present one. Stothert's appli- 

 cation of steam to beds of stones 

 may be thus abridged : — 



For heating Pine Pits. — Figs. 

 23. and 24. represent a mode of 



