1G6 



GARDENING FOE PLEASUEE. 



quarter spans ; " that is, having nearly two-thirds of the 

 roof long on one side and the other one-third on the other. 



The long or two-thirds 

 side should in all cases, 

 as near as possible, slope 

 directly south, the ob- 

 ject being to obtain, dur- 

 | ing the dull days of win- 

 ter, as much sunlight as 

 ^ possible ; and for the 

 ^ same reason the wood 

 workoftheframeshould 

 ^ be as light as possible, 

 g_ and the glass of the 

 1 largest size that can be 

 \ economically used. The 

 average size now in use 

 3 for this purpose is twelve 

 3 by twenty inches, put in 

 J the twelve inch way. 

 w The brand of glass most- 

 & ly used is what is known 

 % as "second quality dou- 

 g ble thick French." It 

 a is of the utmost impor- 

 g tance that the glass be 

 '. clear and without flaws; 

 ^. otherwise the flaws will 

 E concentrate the sun's 

 rays, forming lenses, 

 and burn the foliage. 

 When greenhouse struc- 

 tures are not wanted 

 specially for winter flow- 

 ers or fruit, they may be formed of equal spans, as in 

 figure 55. In this case the ends should face north and 



