BLUE GLASS. 



By Robert Buist, Philadelphia, Pa. 



The use of blue glass for horticultural purposes is not a new idea; 

 the subject received considerable attention in the days of Loudon, and 

 its use was repeatedly advocated through his magazine. It is now 

 freshly before us through the ingenious and well-devised operations of 

 General Pleasanton, of this city, in his grapeiy, and other portions of 

 his establishment. I noticed the effects and results on his in-door grapes 

 about five years ago, by an article in the Gardener's Monthly. Since 

 then, till n^w, the subject has had no attention, though the general's 

 grape vines and crops have been admired by all who visited them. 

 Whether it is the blue glass, the rich, high, and dry borders, or his 

 original method of pruning, that produces the results, I will not now 

 decide. His large grapery has every seventh or eighth row of blue 

 glass, which produces a very agreeable shade all over the strong and 

 healthful foliage, and the rich-colored and luscious fruit, both of which 

 assert the superior effects of this shade of glass. 



Last year I saw in Europe that some of* the most scientific horticul- 

 tural establishments have their propagating glasses and frames all blue 

 glass. In Belgium the very large glass structures had all a shading of 



VOL. IX. 15 225 



