Book II. 



ORNAMENTAL HOT-HOUSES. 



815 



sions (Jig. 571.), is attended with considerable expense, risk of breakage, and what is of 

 still more consequence, risk to the plants, if they happen to be uncovered too soon in 

 spring, or left too long uncovered in autumn, we would recommend the polyprosopic 

 roof (1610. and Jig. 261.) as by far the most perfect description of a hot-house roof that 

 has yet been devised. With such a roof, the plants within may, at any time, in a few 

 minutes, be as completely exposed to air, rain, dew, and sun, if these exist without, as 

 if the roof were removed ; and again, in a few minutes, they may be completely shut up. 

 The improver who shall erect an extensive conservatory of this kind (Jig. 571. a), and 

 apply to it the regulating apparatus of Kewley (Jig. 217.), will find himself in possession 

 of the most unique and complete plant-structure in the world. 



6175. The conservatory in comparatively humble and economical residences (Jig. 572.), 

 may consist of a number of rectangular sashes, connected and supported by means of 

 light iron rafters. In the beginning of summer, the sashes may be removed and applied 



to the ripening of peaches, vines, or figs against walls, or laid over excavations in the form 

 of pits, containing melons, cucumbers, &c. The light iron frame-work may either be 

 removed, or remain, and be disguised by annual creepers, or by vines of the narrow-leaved 

 sorts. Sometimes a cistern is placed in the conservatory for growing aquatics, and 

 containing a few gold-fish ; but as there are very few exotic aquatics which will thrive 

 in the temperature of the green-house, this is seldom requisite, unless as a decoration, 

 and for the use of the water in culture, and the appearance of the fishes. The tempera- 

 ture of conservatories being the same as of green-houses, the same proportion may exist 

 between the flues and volume of air to be heated. 



6176. The dry-stove is chiefly devoted to the culture of succulents. In design it 

 need not differ from the green-house, unless, perhaps, in the stage (Jig. 573. a) being 



placed somewhat nearer to the roof. The name and character of this structure is 

 derived from the higher degree of heat generally kept in it, and from the air being less 

 moist than in the bark-stove, where more water is used, and consequently more vapor 

 generated. The volume of air to be heated by one fire in the dry-stove, should not 

 exceed two thirds of that to be heated in a green-house or conservatory, similarly con- 

 structed and situated. 



