"Yes, but at slow speed. The engines are in better shape now than ever before," Tom said. "Well, if you're ready we'll have breakfast." The meal was served by Koku with as much unconcern as though they were in the Swift homestead back in Shopton, instead of floating near the clouds. And while it was being eaten in the main cabin, and while the crew was having breakfast in their quarters, the aerial warship was moving along over the ocean in charge of George Watson, one of Tom's engineers, who was stationed in the forward pilot-house. "So you're going to give the guns a real test this time, is that it, Tom?" asked Ned, as he pushed back his plate, a signal that he had eaten enough. "That's about it." "But don't you think it's a bit risky out over the water this way. Supposing something should--should happen?" Ned hesitated. "You mean we might fall?" asked Tom, with a smile. "Yes; or turn upside down." "Nothing like that could happen. I'm so sure that I have solved the problem of the recoil of the guns that I'm willing to take chances. But if any of you want to get off the Mars while the test is being made, I have a small boat I can lower, and let you row about in that until--" "No, thank you!" interrupted Mr. Damon, as he looked below. There was quite a heavy swell on, and the ocean did not appear very attractive. They would be much more comfortable in the big Mars. "I think you won't have any trouble," asserted Lieutenant Marbury. "I believe Tom Swift has the right idea about the guns, and there will be so small a shock from the recoil that it will not be noticeable." "We'll soon know," spoke Tom. "I'm going to get ready for the test now." They were now well out from shore, over the Atlantic, but to make certain no ships would be endangered by the projectiles, Tom and the others searched the waters to the horizon with powerful glasses. Nothing was seen and the work of loading the guns was begun. The bomb tubes, in the main cabin, were also to be given a test. As service charges were to be used, and as the projectiles were filled with explosives, great care was needed in handling them. "We'll try dropping bombs first," Tom suggested. "We know they will work, and that will be so much out of the way." To make the test a severe one, small floating targets were first dropped overboard from the Mars. Then the aerial warship, circling about, came on toward them. Tom, seated at the range-finders, pressed the button that released the shells containing the explosives. One after another they dropped into the sea, exploding as they fell, and sending up a great column of salt water. "Every one a hit!" reported Lieutenant Marbury, who was keeping "score." "That's good," responded Tom. "But the others won't be so easy. We have nothing to shoot at."