56 THE PARLOR GARDENER. 



The Cold Portable Greenhouse. 

 The portable greenhouse may be cold ; that is, 

 without any special means of warming it. It may 

 also be tempered ; that is, furnished with an ap- 

 paratus for producing artificial heat. Except for 

 the size and the decoration, more or less elegant, 

 it is nothing more than a great hand-glass,* of 

 which the panes of glass, supported on a light iron 

 frame, are arranged by means of slips of lead. 

 Many of the upper panes should be made to open 

 by sliding, as well to let air into the interior, as 



* HAND-GLASSES Portable frames or covers, formed of iron, 

 zinc, or wood, and glazed. These glasses differ from bell-glasses in 

 being longer and composed of numerous small pieces of glass, which 

 are fastened together by narrow strips of lead. Hand-glasses are 

 generally square; but they may be made of an octagon, or any 

 other shape that may be found most convenient; and they are some- 

 times made with a pane to open to admit air, or with the upper part 

 to take off. This is very convenient; for as hand-glasses are chiefly 

 used for protecting half-hardy plants during winter, it is necessary 

 to give them air every fine day, and it is very troublesome to be 

 obliged to lift the hand-glass off the plant, and to lay it on one side, 

 whenever this is done. Bell-glasses, on the contrary, being princi- 

 pally for preventing the evaporation of moisture from the leaves of 

 cuttings, do not require any opening, as the plants seldom want any 

 air till they have rooted. Mrs. Loudon's Ladies' Companion for 

 the Flower Garden. 



