"Ten miles an hour" reiterated the officer and Dixie recognized a ring on the finger of the hand extended toward Von Lertz. Quickly her hand dropped over the side of the car and for a moment her finger was busy writing in the dust which had collected there, while the now thoroughly incensed German volleyed a heated tirade at the policeman, who contented himself with repetitions of "ten miles an hour's the limit." The attitude of the officer suddenly changed as Dixie's hand was withdrawn into the car and lay idle in her lap. "Oh, all right, if you are going to get mad about it," he said and stepped aside peering intently at the side of the car on which Dixie was seated. Plainly written there were these words: "Will send message boy by tonight. Watch hotel alley." As the machine disappeared in the distance the motorcycle policeman raised his goggles and laughed. It was Harrison Grant. But Heinric von Lertz did not know. Defying the rules of the road he was speeding toward the hotel, his good humor of a few minutes before dissipated by the dispute with Grant. Suddenly the speed of the car slackened but a few doors from the hotel. "Do you know those two men?" demanded Von Lertz. Dixie Mason turned in the direction he pointed. Baroness Verbecht and Madam Stephan were aiding Cavanaugh and Stewart of the Secret Service, both of them apparently intoxicated, into a taxicab standing at the curb. Stewart noticed Von Lertz pointing at them and waved a maudlin salute as he ordered the chauffeur to drive to a roadhouse on the outskirts of Buffalo in a thick loud voice. "Do I know them?" retorted Dixie. "Do you know Harrison Grant?" "Yes, the dog," muttered Von Lertz. "Those are his two best men." "Good," said Von Lertz, smiling happily, "I will commend Verbecht and Stephan in my report." Dixie Mason smiled quietly. She had seen the method in which Secret Service operators acquired "business jags." She had watched operatives recklessly ordering drinks of every description and downing them in gulps, knowing that harmless substitutes had been served by another operative at the bar. "You will have to excuse me," said Von Lertz as they entered the hotel. "I have to supervise arrangements. I will meet you in Verbecht's room at eight o'clock." Dixie kept him well in sight as he turned away and as a result was able to send Harrison Grant the information that Von Lertz and three of Koenig's men had spent the afternoon attaching detonators to sticks of dynamite, by means of the operative in the guise of a bellboy. When she went to the room of Baroness Verbecht at the appointed hour she found Madam Stephan and the Baroness already there. Von Lertz entered a few moments later. "You two here?" he demanded angrily of the female spies. "You left the two Secret Service men to their own devices."