ABSTRACTS OF TECHNICAL ARTICLES 5.17 



posure of the cotton to high atmosi)hcric humidities, is termed transient 

 improvement. 



The effects of ash constituents, other than Na and K, on the insulat- 

 ing properties of cotton are small, and these effects are difficult to 

 evaluate, since they are masked by the effect of atmospheric humidity. 



In this investigation, primary consideration has been given to cotton 

 since it is the most economical material available for use in telephone 

 apparatus insulation, and the improvements in electrical properties 

 secured by water-washing have led to its substitution for silk to a large 

 extent in the telephone industry. 



