In a few minutes they received an urgent summons. They found Mr. Moreton waiting in a large, open car below. He had quite recovered his temper. His face, indeed, shone with the benign expression of a child on its way to a treat. 'Miss de Freyne and Mr. Lavendale, you can sit by my side,' he ordered. 'Jimmy, you get up in front. The man knows where to go.' They swung round and in a few minutes turned into Central Park. At a spot where the road curved rather abruptly, the car came to a standstill. Mr. Moreton stepped out. From his pocket he drew a small skein of what seemed to be white silk, and a tiny instrument with a dial face and perforated with several holes. 'Hold that,' he directed Lavendale. The latter obeyed. Mr. Moreton drew the thread of white silk backwards and forwards through one of the apertures in the instrument, the finger on the dial face mounting all the time from zero. When it reached a certain figure he drew it out, and, stooping down, stretched it across the path from the hedge to the curbstone. Then he glanced up and down and around the corner. The park was almost deserted and there were only a few loungers in sight. From the small bag which he had brought with him in the car, Mr. Moreton next produced a square black box with a handle in the side, and a pair of black indiarubber gloves which he hastily donned. Then, with the box in his hand, he turned the handle which protruded from its side. A queer, buzzing little sound came from the interior, a sound which, low though it was, thrilled Lavendale from its utter and mysterious novelty. It was a sound such as he had never imagined, a sound like the grumblings of belittled and imprisoned thunder. The finger on the dial moved slowly. When it had reached a certain point, Mr. Moreton paused. He clasped the machine tightly in his hands. The mutterings still continued, and from a tiny opening underneath came little flashes of blue fire. The inventor stepped into the car, motioning the others to follow him, and gave an order to the driver. They backed to a spot by the side of the road, about a hundred yards away from where the thread of white silk lay stretched across the pavement. Mr. Moreton gripped the instrument in his rubber-clad hand and leaned back in the car, his eyes fixed upon the corner. His expression had become calmer, almost seraphic. 'We shall see now,' he promised them, smiling, 'another land of dance. There is only one thing I should like to point out. The little instrument I hold in my hand now is adjusted to any distance up to two hundred yards. By turning the handle a dozen more times, the distance could be increased to a mile, and more in proportion. The length of my silk-covered wire is immaterial. It could stretch, if desired, from here to Broadway. Now watch.'