But in guarding a ship, except in very particular and extraordinary cases, it is a custom of the Service merely to sleep out there for the purpose of keeping sightseers from climbing all over it. In many cases it isn’t even guarded at all over night. Who’d want to tamper with an airplane? In moonshine country, or among people who have any possible reason for wanting to harm a ship or a flyer, careful guard is kept, of course. But ordinarily not any more than enough to guard a car. Well, while the Secret Service men were snooping around Boundville and Cleveland, Marston, Fernald, a new mechanic named Gray, shipped on from Langham, and went back to Cleveland to bring the next shipment through. At the depot--Marston not knowing it, of course--was an operative to shadow him every minute. Marston, as a matter of fact, was in rather a bad way. Despite the fact that he had been, as he thought, absolutely whitewashed, he looked more like a sick pup than ever. His physical sickness had disappeared within a few hours almost magically. But mentally he was an invalid still. The Martin factory was heavily guarded, of course. The newspaper stories had been carefully taken care of; just a small item explaining my wreck as due to motor failure, and Fernald’s as the result of a sharp downward current of air over the cool water, which is scientifically possible. No word of the filed wires had got about, nor any connection between the fires and the wrecks. Every laborer under suspicion, by the way, had proved an alibi; which, in a manner of speaking, strengthened the case against Marston. The operatives were tracing his movements the night of the fire, among other things. One ship was ready to ramble when we got there, and it had machine-guns installed in the front observer’s cockpit and also in the radio compartment in the rear of the bomb space. They had been shipped from Dayton, at my suggestion, to help guard the ships if necessary. I wired Washington, and was ordered to proceed with one ship and let Les follow when the second one was completed. Time was getting very precious, there were only two Martins at Langham, and practise must start very soon. Already the brigade would be four ships short--four fewer two-thousand pounders to help sink our battleship. Marston and I took off bright and early one Wednesday morning. Just before we started I got word that Marston had made no suspicious moves while in Cleveland, had not even conversed with a stranger. Nevertheless I said to him just before we started-- “Ride in the front cockpit, will you Marston?” It is less comfortable there than beside the pilot, for the folding observer’s stool has no back to it. He looked at me with haggard eyes and seemed about to protest, but he said nothing.