for all except Odontoglossums, Masdevallias, and others which con- 

 tinue active throughout the year. Non- pseudo-bulbous Orchids must 

 also have a more liberal supply of water than those with pseudo- 

 bulbs, which serve as storehouses of nutriment. In the summer and 

 f rowing season the material on the shelves and the paths must be 

 ept well moistened, and in cool houses shallow tanks should be 

 provided at the sides of tho paths. For supplying the plants and 

 syringing rain water is the best, and it must always be used about the 

 temperature of the house. Hard water should be avoided except 

 for damping purposes, as though lime is not injurious to some Orchids 

 it disfigures the foliage. Baskets and blocks can be dipped, but this 

 must be carefully done with the former, or the drainage may be 

 disturbed. There is some difference of opinion respecting the 

 beneficial effects of syringing, but the majority of cultivators have 

 proved its usefulness, and in some large trade establishments the 

 plants are syringed most liberally, ordinary watering-cans being 

 seldom used. Morning and evening syringings in the spring, summer, 

 and autumn are beneficial to growing Orchids, but care must be 

 exercised to keep the water off the flowers, and as much as possible 

 off young tender growths, particularly those of Laelias like L. 

 purpurata ; while in the winter it should be discontinued, especially 

 when the weather is severe. At St. Albans a simple and labour- 

 saving mode of damping the houses is adopted, which is, however, 

 only suitable for large establishments. Under the stages and along 

 the paths in every house are taken two or more pipes 1 inch in 

 diameter, which are perforated at short intervals and connected with 

 the main supply, so that by turning taps in convenient positions the 

 whole house or auy portion can be quickly damped with little trouble. 

 The atmosphere of Orchid houses must be constantly moist, and 

 in hot weather this can only be effected by a frequent and liberal 

 distribution of water upon the paths and stages. A useful instrument 

 for determining the amount of moisture in the air is the hygrometer, 

 consisting of two thermometers graduated exactly alike, with small 

 projecting bulbs. These are affixed an inch or two apart to a porce- 

 lain or other frame, and the bulb of one is connected by a little 

 syphon of cotton, or lamp-wick, with a small bowl kept constantly 

 filled with water. The evaporation of water from the latter, termed 

 the wet bulb, by the extraction of heat, causes the mercury to fall, 

 and by comparing the temperature thus registered by that shown in 

 the dry-bulb thermometer, which indicates the temperature of the 

 hou>e, it is seen at a glance whether the air is dry or moist. When 

 saturated with moisture the mercury in the two tubes will stand at 

 the eame level, and the drier it is the greater will be the difference 

 between them. This simple instrument can be easily constructed 

 if two evenly balanced thermometers are obtained, but they can now 

 be purchased very cheaply, and should be employed wherever Orchids 



