But all hilarity disappeared the moment the receiver of her 'phone slipped gently into its hook. It was lifted very shortly and the voice of Dixie Mason, having called her number, was carried to the ear of the Chief of the Secret Service. A quick conversation followed. "I will have men at Harden's Corner. Did you get that? Harden's corner," he spoke in final tones. "Give them the signal I have just told them they would get from you. Everything straight? All right. Good bye." Dixie pushed the 'phone from her. "Mamette! Hurry! The motor togs!" For the next half hour Dixie was extremely busy, and Mamette's services had to be called upon to assist in the unusual toilette she was making. Although Heinric von Lertz, calling shortly to convey his regrets at the necessity of breaking his engagement with her for the motor trip they had planned, found her entrancingly gowned in a dark negligee, the door had hardly closed behind him, when the entrancing negligee slipped to the floor and disclosed Dixie Mason in motor clothes of an extremely mannish cut. Calling directions into the bemuddled ears of Mamette, donning goggles and cap at the same time, she hurried to the hall and into the elevator. As the machine of Heinric von Lertz, carrying with him Von Papen, and Boy-Ed, crossed the street intersection beyond on their way to Long Island, Dixie Mason's car fairly leaped out of the driveway and on to the road they were taking. Across the city and over the bridge the big car with the small one following at a discreet but never faltering distance, took its way. At the bridge it was joined by the heavy wireless automobile carrying Wolff von Igel and a driver. Then out on the broad Long Island road with the course spreading smooth and straight before them. The spies were looking for a point of vantage in the hills where their wireless could be used to catch the messages going out from Sayville to the sugar ships in danger. Dixie Mason was looking for a well known intersection of roads, where a road came down from a hill and cut sharply across the high road--a road well hidden except for its intersection. Her sharp eyes travelling beyond caught a glimpse of the white cross formed by the roads. Two long shrill wails followed by three short ones pierced the air, above the steady drumming of the heavy cars ahead. The cars containing Von Lertz and Von Papen, Von Igel and his driver dashed past the intersection of the road where a tall signpost bearing the information that this was Harden's Corner reared itself. To the men in the cars the sign meant nothing, but to Dixie Mason it meant success or failure. A moment of suspense for her followed, and then a machine dashed into the road between her car and the cars ahead. Dixie slowed down. Her services were not needed now. The other Secret Service operatives would complete her work for her, but hoping to see the finish she drove on slowly.