"One is a son of Admiral Trefusis; his companion is, I believe, also a son of a distinguished English naval officer."
"Well, and what of it?" asked von Ruhle.
"Hostages," replied the doctor briefly. "Later I will explain. Meanwhile we'll carry them to the cave. It's farther than back to the ruins; but perhaps, as young Trefusis said, there may be a search-party, and the ruins would be one of the first objects of investigation."
Although, with the exception of periodical visits abroad, Dr. Ramblethorne had lived in England all his life and was a fully qualified medical man, he was a highly trusted and talented agent of the German Secret Service. Months before the outbreak of war, he had been ordered to report upon the defences of Devonport, and in order to do this he had bought a practice on the outskirts of Plymouth. Upon the commencement of hostilities, he was detailed to keep under observation the military preparations of the Duchy of Cornwall, and also to take necessary steps for communicating with German submarines that, under von Tirpitz's prearranged scheme, were to operate in the Bristol Channel. Von Ruhle was one of the few subordinates he actually knew. There were others with whom he communicated only through an intermediary, and who knew him only by a number.
Von Ruhle was almost as mentally clever as his superior. Ostentatiously he was an Englishman. Sometimes he posed as a mining engineer; at others as a commercial traveller; as an accredited representative of the British Red Cross Society he was in the habit of making frequent journeys to Holland, presumably in connection with work at Groningen Internment Camp. At the present time, his activities were centred upon the formation of a secret petrol depot for the supply of fuel to unterseebooten operating in the Bristol Channel and off the south coast of Ireland.
A couple of slight incidents had served to put the cautious Ramblethorne on his guard during his interview with von Ruhle in the ruined chapel.
Although he verbally deprecated his subordinate's alarm when the lads accidentally dislodged a stone from the tower, it was merely to disarm possible eavesdroppers of any suspicion that their presence was suspected.
The ability to control his feelings was one of the super-spy's chief assets. Suspicion once aroused, he proceeded without the faintest sign to investigate his surroundings. His keen eye soon lighted upon the lads' sweaters. Then it was that an adjournment was suggested to Main Beach Cove.
This was simply and solely a "blind", for on gaining the cover of the boulder-strewn hillock the doctor communicated his suspicions to his companion. The pair then crouched behind the rocks, whence they were able to command a view of the tower.
It was not long before their enterprise met with success. They saw Trefusis and his chum cautiously descend by means of the ivy; then, directly the lads set out upon their ill-starred tracking expedition, the Germans, as before related, succeeded in outflanking them and effecting their capture.