HOW TO SHADE C'ARXATTONS. 55 



sun for a week or ten days. A deep shading for the glass, lasting 

 a briet period, is made of lime and water, or yellow clay, thinned 

 with water, strained and applied with a brush or spray pump. A 

 more permanent shading is made of naptha and white lead, re- 

 duced to the appearance and consistency of skimmed milk, applied 

 moderately at first, and deepened as the sun in the spring gains 

 power. 



I quote from M. G. Kains, a very intelligent view on shading 

 glass over carnations with preparations of lead and the means to 

 be used in removing the same. 



* 'The removal of white lead from greenhouse roofs is a tedious 

 and more or less difficult job The florist should welcome any 

 method that will lighten this labor and reduce the risk of the 

 breakage of glass. When this shading is to be applied as a liquid 

 with naptha, by means of a spray pump, the powdered paint 

 should be purchased; not the paint as it is usually bought in drums 

 or cans. If the latter be used the shade will be much harder to 

 remove in any case, and the method of removing it described be- 

 low will work much less effectively. The reason for this is that 

 the oil in the mixed paint forms a coating of itself upon the glass, 

 independent of the lead , and is not acted upon by the acetic acid 

 used to remove the lead, only a portion of which can be reached. 

 If adulterated white lead be used the recipe will be useless, be- 

 cause the adulterant commonly used in white lead is barium sul- 

 phate, a substance not soluble in acetic acid. 



When pure lead is used, mix one part of strong vinegar to 

 four of water, or one part of acetic acid to about fifteen of water, 

 and apply with a fine nozzle direct to the roof. If any drips down 

 it may be used over again since it will have been applied too copi- 

 ously. Some of the white lead will have been dissolved in this 

 drip and it will not be quite so effective a second time. After ap- 

 plication, the usual rubbing may commence, when it will be found 

 that the shade will come off much more easily. The reason for 

 this is that the white lead is changed from the basic carbonate to 

 the acetate, which is very soluble in water. Water coupled with 

 friction will, therefore, easily remove it." 



