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VEGETABLE GARDENING. 



stitutes for glass. Such covering, however, will not allow the 

 sun's rays to penetrate it easily nor is it so effective in prevent- 

 ing radiation of the heat as glass, but under some circumstances 

 it may be very desirable. Sash thus covered may often be used 

 to advantage in the latter part of spring by alternating it on 

 the frames and thus doubling the amount of sash at small ex- 

 pense. Or, they may be used in the warm weather of spring 

 when the sash needs to be removed entirely in the middle of the 

 day. They are excellent for. covering beds filled with recently 

 transplanted crops, since the light is less intense and evapora- 

 tion less under them than under glass. A convenient way of 

 forming these sashes is to make frames without sash bars but 

 with one or two wires stretched across them to support the cloth 

 or paper covering. Unbleached heavy cotton cloth may be used 

 for this purpose, and the material for dressing it should be made 

 of three pints pale linseed oil, one ounce acetate of lead and 

 four ounces white resin. Grind the acetate in a little oil, then 

 add the resin and the rest of the oil. Melt in an iron kettle 

 over a gentle fire until well mixed and apply warm to the cloth. 

 When paper is used it should be what is known as manilla 

 wrapping paper. Paste this firmly and tightly on the frame with 

 fresh flour paste. Dry in a w^arm place. Then wipe the whole 

 of the paper with a damp sponge to cause it to stretch evenly. 

 Dry it again, and apply boiled linseed oil to both sides of it and 

 dry in a warm place. Use linseed oil that is free from cotton 

 seed oil. 



Shading the Glass. — In the hot weather of late spring or sum- 

 mer the sunlight is too warm for many plants in the greenhouse 

 and it is customary to shade them. The amount of shade neces- 

 sary will depend somewhat on circumstances. This shade may 

 consist of lath screens laid on the roof, but more commonly it 

 is given by sprinkling the glass on the outside, w^ith a wash 

 made of white lead and gasoline, put on with a spray pump or 

 syringe. This is easily and cheaply done. It will generally 

 come off by autumn or may be rubbed off with a coarse rag or 

 brush. Whitewash is sometimes used for this purpose but it 

 is too easily washed off by heavy rains to be desirable. 



