On arrival at New Stone Buildings I telephoned to Bruton Street, but Chapman, his valet, told me that his master had slept there only one night, had received a visit from a respectably dressed middle-aged woman, and had gone away--to an unknown destination. Therefore I waited for a whole week in anxiety and suspense, until one morning I received a wire from him, despatched from Kirkcaldy, urging me to join him at once at the Station Hotel in Perth. Next morning at nine o'clock I was seated on the side of his bed, telling him of the incident of the lamp. "Ah!" he exclaimed after a pause. "My surmises are slowly proving correct, Jack. You must buy a bicycle-lamp down in the town and a piece of green glass. To-night you must go there at the same hour and show a similar light. The matter seems far more serious than I first expected. The enemy is no doubt here, in our midst. Take this. It may be handy before long," and he took from his kit-bag a new .32 Colt revolver. By this, I saw that he had resolved upon some bold stroke. That evening, after an early dinner at the hotel, we took train to North Queensferry, and on alighting at the station he sent me up to the golf-links to show a light for half an hour; promising to meet me later at a certain point on the road to Rosyth. I gained the lonely spot on the golf-course and duly showed the light. Then I hastened to rejoin my friend at the point he indicated, and found him awaiting me behind some bushes. Almost at the moment we met, a female figure came along beneath the shadow of a high wall. She was a poorly dressed girl, but the instant she addressed my friend I recognised by her refined voice that it was Vera, the dainty daughter of the Admiral Superintendent. "Elsie is waiting down by the Ferry Barns," she said quickly, in a low whisper, after greeting me. "Heinrich has not kept his appointment with her." "You have the note?" he asked. "Recollect what I told you concerning the man Hartmann." "Yes," she replied. Then, addressing me, she said, "Take care of these people Mr. Jacox. They are utterly unscrupulous"; and she again disappeared into the darkness. Ray and I turned and again walked back in the direction of Rosyth. But when we had gone a little distance he told me to approach the naval offices carefully, conceal myself in the bushes, and watch until he joined me. On no account was I to make any sign, whatever I might witness. Though intensely cold the night was not very dark, therefore I was not long in establishing my position at a spot where I had a good view of the offices. Then I leaned upon a tree-trunk and waited in breathless expectation. I touched my father's old repeater which I carried and found it to be a quarter past midnight. For over an hour I remained there, scarce daring to move a muscle.