How they tested the cable during laying: > At least once in every five minutes the cable was used as a condenser. A charge from a battery of about one hundred

How they tested the cable during laying: > At least once in every five minutes the cable was used as a condenser. A charge from a battery of about one hundred cells was given and in turn discharged through a properly shunted Sullivan galvanometer and the “throw” of the needle carefully noted. Note that “condenser” means “capacitor”. —- Another good read is the biography of Oliver Heaviside who is famed for his (armchair) contributions to both wireless and subsea communications!