67 



is rarely found necessary to use the plugs mentioned. For tropical 

 Orchids of the Cattleya and Phalsenopsis type the ordinary close 

 g'az'mg is preferable, and the ventilation can be satis factorily 

 arranged in other ways, as will be described under that head. It is 

 important to avoid drips, as these are often destructive to Orchids, 

 dn<l the strongest plants soon suffer if exposed to them. Rafters are 

 grooved the whole length to take off the condensed moisture that 

 accumulates along the bars, but the most effective method is to have 

 a narrow piece of zinc screwed or nailed to the under side of the 

 rafters, and bent so as to form, a little channel that will readily 

 convey the condensed moisture to the lowest part of the roof. 



The houses may be epan-roofed or lean-to, according to con- 

 venience, and the aspect is not of very much importance, though the 

 former may preferably run north and south for tropical Orchids, thus 

 giving an east and west aspect for the two slopes, lean-tos for a 

 similar purpose running east and west, with the slope to the south, or 

 for cool Orchids to the north. A north aspect is not essential for 

 cool Orchids. East or west, or indeed any aspect except direct south, 

 can be made to suit them ; bat the more exposed these plants are to 

 the rays of the sun in summer the greater the attention they will 

 need in supplying them with water, nnd it is also frequently difficult 

 to prevent the temperature rising unduly high; otherwise they 

 must have the lightest position possible, and dark corners, or 

 those much shaded by trees, should be avoided. Houses of 

 moderate breadth and height are the best for most Orchids, but 

 Cattleyas and Lselias thrive in lofty spacious structures better 

 than other plants, and seem to prefer such houses, as can be 

 seen in the cases of the two magnificent Cattleya houses at Mr. VV. 

 Lee's and Messrs. J. Veitch & Sons', the latter being probably the 

 largest house devoted to Orchids in this country. It is 132 feet long, 

 22 feet wide, and 11 feet high in the centre ; and the plants are all 

 in capital condition. In private collections, however, some of the 

 best grown plants are seen in small houses, and for cool Orchids 

 they are now generally employed with the roofs pitching on to 

 the eaves nearly level with the side stage, thus dispensing 

 with side lights. For small-growing Odontoglossums and Masde- 

 vallias these are very suitable, but for taller plants and in 

 warmer houses side lights are advisable, as they give greater spaoe for 

 arranging them and admit more light. A span-roofed house intended 

 for a large miscellaneous collection of Orchids should be in two or 

 more divisions according to its size, and the kinds of plants that 

 are to be culiivated having the warmest division at the boiler end, 

 and the coolest can be employed for Odontoglossums or plants in 

 flower, as the blooms last much longer in a lower temperature and 

 less moisture. A well built lean-to frame against the side of such a 

 house can be used for Odontoglossums if sufficient piping be supplied 



