The Problem of Increasing Human Energy
The Problem of Increasing Human Energy Simplified
Part 9
First Efforts To Produce The Self-acting Engine →
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Part 10
Transmission Through The Earth Without Any Wire →
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Part 11
Wireless Telegraphy And The Secret Of Tuning →
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Part 12
Development Of A New Principle—the Electrical Oscillator →
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Part 13
Transmission Of Electrical Energy To Any Distance Without Wires →