132 PORTABLE, TEMPORARY, AND MOVE ABLE STRUCTURES. 



such trees often suffer as much from the glare of the sun and the force 

 of driving winds as from frosts. Those structures used for the more 

 tender plants may be filled with straw or hay, provided the plants are 

 on a lawn where grass seeds dropping from the hay will not prove in- 

 jurious ; or they may be covered with mats or canvas. Besides these 

 forms, which may be made of any size, according to that of the plants 

 to be protected, small semi-globular, close- woven chip baskets, not above 

 a foot high, are used at Abbotsbury as shades for delicate Alpine plants 

 in sunny or windy weather. Where baskets of this kind cannot be 

 conveniently procured, very good substitutes may be found in bast 

 mats, canvas, or oil-cloth, supported by rods forming skeletons of 

 suitable sizes and shapes. 



As hand-glasses, from their great liability to breakage and the 

 quantity of the glass they contain compared with the ground they 

 cover, become very expensive articles, cheaper substitutes may be men- 

 tioned. A common square hand-glass, it has been shown by Mr. Forsyth, 

 * Gard. Mag.' 1841, contains seven square feet of glass to light or 

 shelter two and a quarter square feet of ground, being a little more 

 than three times as much as is really necessary for the plants usually 

 cultivated under them : hence he proposes to substitute boards well 

 painted, pitched or tarred, to increase their durability, in place of 

 upright glazed sides to the hand-glass ; and instead of a conical or 

 pyramidal roof, to employ a square cast-iron sash, twenty-four inches 

 on the side. Fig. 106 shows the sash glazed with small panes, say 

 Fig. 105. 



Fig. 106. 



Fig. 107. 



Hand-box, as a substitute for a 

 hand-glass. 



Sash, as a substitute 

 for a hand-glass. 



Side view of hand- 

 box. 



four inches and a half wide, on account of their cheapness and 

 greater strength than larger- sized panes. The frame, fig. 105, may 

 be six to nine inches high in front, and from fifteen to eighteen 

 inches high at back. These small sashes, when not wanted for hand- 

 glasses, or rather hand-frame coverings, Mr. Forsyth proposes to use 

 as roofing to peach-houses, vineries, &c., and for various other pur- 

 poses ; and he anticipates, and we think with reason, great economy 

 from their adoption in gardens. Fig. 107 is an end view of the box, 

 showing the uprights at the angles for supporting the sash, either 

 close over the box, or raised to different heights to admit more or 

 less air. By means of the notched uprights, the sash may either be 



