The look she gave him somewhat dampened his rashness. She did not speak, but her eyes were enough to nonplus the young gentleman utterly. He made haste to change the subject. In spite of the seeming obstacle imposed by this young girl, the intimacy between Cantor and Potter not only continued, but increased, but beyond a certain point it did not go--and that point was any disclosure of what Potter was doing or how he was doing it. There, though Cantor veered up to the subject obliquely, Potter became filled with reserves. Cantor was unable to say of his own knowledge whether Potter was working on an aeroplane or a toy piano. One other point is to be noted. The men who worked with Potter in the hangar were not strangers, not picked-up mechanics, but men whom he had known for years and trusted. Not one of them but was American-born, and though numerous individuals, presenting impeccable recommendations, applied from time to time for work with him, none was placed. His was a small, compact enterprise, and he was able to keep it under his eye. Though he scarcely considered himself of enough importance to attract the attention of the German spy vermin, he took his precautions as though he were of first interest to them. He believed in insurance. In the latter part of the year Potter was visited more than once by officers wearing the insignia of the Signal Corps, Major Craig among them. To these men, at any rate, he was of importance, not so much, perhaps, for what he was doing at the time as for the potentialities of the future. The heir to the Waite Motor Company's resources was a man of value.... But as 1916 became venerable and neared its end, they were compelled to admit his present consequence. "I believe," said a young captain to Major Craig, "that young Waite in Detroit knows more about aeroplanes, and more about this country's equipment to produce them, than any other living man." "Unquestionably," said the major. "He has made it his sole business to become that man." "Have you seen his engine?" "No--only drawings; but he has added valuable ideas. He has studied, and I can safely say that his motor will be watched for with considerable impatience. It has qualities." "Most enthusiastic man I ever met," said the captain. "It's a fetish with him." "It's a religion," said the major, "and that is something mighty different." Then: "He worries me sometimes. Something unpleasant has happened." Late in November the new engine was assembled, not completed, probably, as it would be manufactured, but perfected to a point where it deserved a trial. Potter prepared for the test and, when all was in readiness, wired Major Craig....