116 GREENHOUSES 



almost proof against decay, but since the 

 joints must be coated with a thick paint 

 when the house is erected, and as the wood- 

 work is preferably white in order to make the 

 house as light as possible, the extra expense 

 involved is hardly warranted. Creosote also 

 has a somewhat poisonous effect on some 

 greenhouse plants. 



If the woodwork has not been primed 

 when received, it is preferably so treated be- 

 fore it is erected. Either pure, thin linseed 

 oil, or a mixture of oil and yellow ochre is 

 used for this purpose. As soon as erected, 

 the whole framework is painted inside and 

 out before glazing. After glazing another 

 coat is applied. Because "of the frequent 

 painting necessary, it is seldom advisable at 

 the time of erection, to apply more than two 

 coats in addition to the priming coat. 



Paints for Iron Work. Ordinary paints 

 which are used for wood may also be used on 

 most unpolished metals. The oxidization of 

 iron and steel, however, is likely to stain 

 white paint, unless these metals are first 

 given a coating to prevent it. A good paint 

 for this purpose may be made by melting to- 

 gether three parts of lard and one part of 

 powdered resin. This is brushed on in a thin 



