American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 641
covering. One object in using several layers of gutta-percha, in the construction ofthe cable, is that, in the process of covering the wire with that material, air holes areliable to occur. If but one layer were used it is evident that the de /elopment of anair-hole into a fault would speedily…
Telegraph
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