Just at present Gerda's behaviour was perfectly orthodox. If she went on the warren, it was invariably as one of a "threesome", and the chums could detect her in no more solitary and clandestine excursions. She seemed to have assumed a sudden interest in salvaging, and particularly in the beacon which the girls were beginning to build upon the headland. No one was ready to work harder in carrying up the pieces of driftwood from the beach, and piling them on to the great stack which every day grew a little higher and higher, till it really began to be a conspicuous object, and could be seen from both the villages of Pontperran and Porthmorvan, and from the sea. It was at Gerda's suggestion that a Union Jack, fastened to a pole, was kept flying from the top--a little piece of patriotism which appealed to the school at large, though it roused suspicion in the minds of the chums. "It's a signal, of course," said Dulcie. "Some fine day she'll pull it down, and substitute the German flag," agreed Deirdre. "She's only waiting her opportunity." "Unless we circumvent her. There are two Britishers here who mean to look after their country!" It was curious how many little things, really quite trivial in themselves, seemed to point in the direction of the chums' fears. Miss Birks greatly encouraged a debating society among her girls, and on her list of subjects for discussion had placed that of "National Truth versus Diplomatic Evasions". Gerda had certainly been chosen to speak for the opposition, and was therefore pledged to the side of diplomacy; but Deirdre and Dulcie thought she made far too good a case of it, and pleaded much too warmly the cause of the ambassador who on behalf of his country's honour is obliged to meet guile with guile, and outwit the enemy by means of stratagems and deeply-laid schemes. "Any expedient is allowable for the sake of your fatherland," she had contended, and Dulcie quoted the words with a grave shake of her head as she talked the matter over with Deirdre. "Notice particularly that she said fatherland! Now the Vaterland is always Germany. She didn't mean Britain, you may depend upon it. No--she's planning and scheming for another war!" "Then we'll plan and scheme for King George! We'll accept her principles, and 'make use of any stratagem to outwit the enemy'." So they waited and watched, and watched and waited, in what they flattered themselves was true Machiavellian style, till they were almost growing tired of so fruitless an occupation.