With his three associates, one of whom was an ex-telegraphist of the post-office at Aranjuez, near Madrid, Martin had come to England, having purposely followed Falconer from Paris, knowing him by repute as a Marconi engineer.
His movements had at first been closely followed, for the Metropolitan police had been warned of Martin’s arrival, and he had been shadowed to Hertford Road by a girl in the employ of Scotland Yard. But afterwards, so honest did the man appear, that the surveillance had been dropped, and it had remained to Geoffrey to investigate the plot.
Martin had, as it was afterwards proved, bought in Chalk Farm Road certain component parts of a very sensitive and up-to-date appliance for tapping the land-line from London to Poldhu, which runs from Plymouth to St. Austell, and past Miss Trethowen’s house to Truro and Poldhu.
By tapping the trunk telegraph wire that night Martin had been able, by a very ingenious arrangement which Falconer afterwards examined, to despatch an urgent message to Poldhu just as though it had been received over the counter in the office in Fenchurch Street, in London, and tapped out from Marconi House. Thus the conspirators had been able to interpose a false message which they intended should be sent by wireless from Poldhu to Madrid.
The whole plot was extremely cleverly conceived, for on that night, just before Hamilton rang up Poldhu, they had sent instructions in code presumably from the London office in Lombard Street to the head office in Madrid ordering the bank to pay to a certain Señor Alfonso Fonesca, living in the Calle Zorilla, in Madrid, the sum of thirteen thousand five hundred and eighty pounds sterling at the current rate of exchange.
Needless to record, the false message which had been so cleverly imposed upon the land-wire was never dispatched from Poldhu, for that night all messages had been suspect, and the one in question was held back.
At the time of writing, Martin—who at the Court Assizes at Bodmin was proved to be a Swiss subject—is serving a term of seven years’ penal servitude, as well as his three companions, all of whom were Belgians.
Happily the bogus message they sent from Tregoney did not, as they hoped, pass through the “Devil’s Oven” and out into Space. So the bank was saved a theft of nearly fourteen thousand pounds.