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140 in the distances over which it is possible to communicate; this result being due, no doubt, to the much greater length of wave radiated by the big elevated conductor of the long-distance stations, compared with the shorter wave-length radiated by the smaller and less powerful installations. Thus messages were received from Poldhu at the positions marked on the map (fig. 13), which is a copy of the map accompanying the official report of the experiments. These positions, at which signals were received direct from Poldhu, are in the Baltic near Sweden, at Kiel, the North Sea, the Bay of Biscay, also Ferrol, Cadiz, Gibraltar, Sardinia, and Spezia. Messages were received distinctly in these places from Cornwall, although, in the Baltic,

the whole of England, the Netherlands, and part of Germany and Scandinavia lay between Poldhu and the Carlo Alberto. Also, at Cadiz and Gibraltar the whole of Spain intervened; and at Spezia and Cagliari, in the Mediterranean, the whole of France, including the Alps, lay in a direct line between the two stations.

After these experiments the Carlo Alberto was sent back from the Mediterranean to Plymouth, and thence conveyed the author to Canada; and in October, 1902, signals from Poldhu were received on board ship throughout the voyage up to a distance of 2,300 miles.

In December, 1902, messages were exchanged between the stations at Poldhu and Cape Breton, but it was found that communication was better from Canada to England than in the opposite direction.