100 GREENHOUSES 



to which wire netting has been blown is 

 sometimes used. Ground or frosted glass is 

 occasionally used in palm-houses or ferneries, 

 where a soft, subdued light is desired. This 

 effect is more commonly obtained by paint- 

 ing or whitewashing the clear glass and vary- 

 ing the thickness of the coating according to 

 the season of the year. 



Size of Glass. The size of the glass varies 

 according to the purpose for which the house 

 is to be used, and the taste and personal pref- 

 erence of the owner. Where extreme light- 

 ness is wanted, large panes are used thus 

 diminishing the number of sash bars. There 

 is, however, a practical limit to the size. Glass 

 increases rapidly in price as the size in- 

 creases, and the large panes break more 

 easily. Moreover, the size of the sash bars 

 must be increased to carry the extra weight, 

 and every increase in their size means more 

 shade. 



Of 136 practical growers consulted on this 

 point, 108, or nearly 80 per cent., favored 

 either 16 x 20 or 16 x 24-inch glass with the 

 longer edge parallel to the sash bar. That 

 is, the great majority preferred to have the 

 sash bars spaced about 16 inches apart. 



