THE REMOVAL OF STAINS 243 



tected by the band retains its fresh appearance because the 

 light has not had access to it. Silks and other fine fabrics 

 bleached in this way fade with age, and assume an unnatural 

 color. One reason for 'this is that the dye used to color the 

 fabric requires a clear white background, and loses its charac- 

 teristic hues when its foundation is yellow instead of white. 

 Then, too, dyestuffs are themselves more or less affected by 

 light, and fade slowly under a strong illumination. 



Materials which are not exposed directly to an intense and 

 prolonged illumination retain their whiteness for a long time, 

 and hence dress materials and hats which have been bleached / 

 with sulphurous acid should be protected from the sun's glare) 

 when not in use. 



223. The Removal of Stains. Bleaching powder is very 

 useful in the removal of stains from white fabrics. Ink spots 

 rubbed with lemon juice and dipped in bleaching solution 

 fade away and leave on the cloth no trace of discoloration. 

 Sometimes these stains can be removed by soaking in milk, v 

 and where this is possible, it is the better method. 



Bleaching solution, however, while valuable in the removal 

 of some stains, is unable to remove paint stains, because paints 

 owe their color to mineral matter, and on this chlorine is 

 powerless to act. Paint stains are best removed by the ap- 

 plication of gasoline followed by soap and water. 



