2044. The orangery with an opaque roof and glass sides was the next step made in the construction of plant-houses; and buildings of this description are still frequently to be met with, as shown in fig. 594., in which an opaque-roofed orangery is shown in combination with two modern curvilinear glass hothouses. Such was the greenhouse in the Apothecaries' garden at Chelsea, mentioned by Ray, in 1684 (Letters, p, 174.), as being heated by hot embers put in a hole in the floor; a practice still extant in some parts of Normandy, and to which, as is well known, the curfew, or couvrefeu bell refers. The same general form of house, with the addition of a furnace or oven, is given by Evelyn in the different editions of his Kalendarium.