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BELL SYSTEM TECHNICAL JOURNAL 



The influence of material on G, while not great, gives the chief 

 justification from the electrical standpoint for employing the better 

 but more costly glasses. 



Conclusion 



Description of Neiv Insulators. Two new insulators are available 

 for use on carrier circuits of the Bell System. These replace the 

 standard D. P. insulator of Fig. 1 in those cases where the additional 

 expense of the new insulators is justified. 



\ 



\ 



\ 



10 



20 



30 



40 



50 



FREQUENCY-KILOCYCLES 



Fig. 23 — Relative leakage of D. P., C. W. and C. S. insulators as measured at 

 Phoenixville, Pennsylvania, in moderate rain. 



One of the new types is designed for use on the wood pins of existing 

 lines. It is known as the C. \V. insulator and its design is shown in 

 Fig. 3. The pair of pin thimbles illustrated at the bottom of that figure 

 is first placed over the two wood pins, then the insulators are screwed 



