[Illustration: Eight-Inch 10,000-Volt Arcs Burning the Air for Fixing Nitrogen.]
[Illustration: Machine for Burning the Air with Electric Arcs so as to Produce Nitrates.]
In this way the power of Niagara has become a factor in the food question, a defence against the ultimate hunger of the human race. And when we think of the hundreds of other great waterfalls to be utilised, and with our growing knowledge of electricity this utilisation will become steadily cheaper, easier, it would seem that the inventor had already found a way to help the farmer. Then there is the boundless power of the tides going to waste, of the direct rays of the sun utilised by some such sun motor as that described in another chapter of this book, which in time may be called to operate upon the boundless reservoir of nitrogen in the air for helping to produce the future food for the human race.
_January 18, 1903, marks the beginning of a new era in telegraphic communication. On that day there was sent by Marconi himself from the wireless station at South Wellfleet, Cape Cod, Mass., to the station at Poldhu, Cornwall, England, a distance of 3,000 miles, the message--destined soon to be historic--from the President of the United States to the King of England._]
No invention of modern times, perhaps, comes so near to being what we call a miracle as the new system of telegraphy without wires. The very thought of communicating across the hundreds of miles of blue ocean between Europe and America with no connection, no wires, nothing but air, sunshine, space, is almost inconceivably wonderful. A few years ago the mere suggestion of such a thing would have been set down as the wildest flight of imagination, unbelievable, perfectly impossible. And yet it has come to pass!
Think for a moment of sitting here on the shore of America and quietly listening to words sent _through space_ across some 3,000 miles of ocean from the edge of Europe! A cable, marvellous as it is, maintains a real connection between speaker and hearer. We feel that it is a road along which our speech can travel; we can grasp its meaning. But in telegraphing without wires we have nothing but space, poles with pendent wires on one side of the broad, curving ocean, and similar poles and wires (or perhaps only a kite struggling in the air) on the other--and thought passing between!