Now that the Liberty Loan drive had somewhat slackened, Ned had more leisure time, and he spent parts of his days and not a few of his evenings at Tom Swift's. Mr. Damon was also a frequent visitor, and he never tired of viewing the tank. Every chance he got, when they tested the big machine in the large field, so well fenced in, the eccentric man was on hand, with his "bless my--!" whatever happened to come most readily to his mind. Tom, now that his invention was well-nigh perfected, was not so worried about not having the tank seen, even at close range, and the enclosure was not so strictly guarded. This in a measure was disappointing to Eradicate, who liked the importance of strutting about with a nickel shield pinned to his coat, to show that he was a member of the Swift & Company plant. As for the giant Koku, he really cared little what he did, so long as he pleased Tom, for whom he had an affection that never changed. Koku would as soon sit under a shady tree doing nothing as watch for spies or traitors, of whose identity he was never sure. So it came that there was not so strict a guard about the place, and Tom and Ned had more time to themselves. Not that the young inventor was not busy, for the details of shipping Tank A to France came to him, as did also the arrangements for making others in this country and planning for the manufacture abroad. It was one evening, after a particularly hard day's work, when Tom had been making a test in turning the tank in a small space in the enclosed yard, that the two young men were sitting in the machine shop, discussing various matters. The telephone bell rang, and Ned, being nearest, answered. "It's for you, Tom," he said, and there was a smile on the face of the young bank clerk. "Um!" murmured Tom, and he smiled also. Ned could not repress more smiles as Tom took up the conversation over the wire, and it did not take long for the chum of the youthful inventor to verify his guess that Mary Nestor was at the other end of the instrument. "Yes, yes," Tom was heard to say. "Why, of course, I'll be glad to come over. Yes, he's here. What? Bring him along? I will if he'll come. Oh, tell him Helen is there! 'Nough said! He'll come, all right!" And Tom, without troubling to consult his friend, hung up the receiver. "What's that you're committing me to?" asked Ned. "Oh, Mary wants us to come over and spend the evening. Helen Sever is there, and they say we can take them downtown if we like." "I guess we like," laughed Ned. "Come along! We've had enough of musty old problems," for he had been helping Tom in some calculations regarding strength of materials and the weight-bearing power of triangularly constructed girders as compared to the arched variety. "Yes, I guess it will do us good to get out," and the two friends were soon on their way.