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A point of great importance would be first to know: what is the capacity of the earth? And what charge does it contain if electrified? Though we have no positive evidence of a charged body existing in space without other oppositely electrified bodies being near, there is a fair probability that the earth is such a body, for by whatever process it was separated from other bodies - and this is the accepted view of its origin - it must have retained a charge, as occurs in all processes of mechanical separation.

Nikola Tesla (2013). “The Nikola Tesla Treasury”, p.283, Simon and Schuster
A point of great importance would be first to know: what is the capacity of the earth? And what charge does it contain if electrified? Though we have no positive evidence of a charged body existing in space without