They made a tour of the rolling shop, the pressing shop, the foundry, and other departments. Although in every case the plant was up-to-date, there was nothing to cause Peter to show any surprise. He had seen similar machines at Dartmouth Engineering College and at the various Royal dockyards. Presently they arrived at a large galvanized-iron building, enclosed by a massive wall of earth. "This is part of the oil-fuel distillery," announced Uncle Brian. "Here we have stored about 50,000 gallons of kerosene, conveyed by pipe-line from the wells at Tajeco, about fifty miles from here. From this tank it passes into an apparatus in yonder building to have the flash-point raised to something like 200° F." "Then what good is it?" asked Peter. "Better than before for aeroplane engine work," replied his uncle. "All our motors are kerosene fired. We don't use petrol. And kerosene with a high flash-point is practically non-inflammable." "And consequently non-explosive," added Peter. "Precisely. That's where safety comes in. Roughly, eighty per cent of fatal accidents to flying men at one time were attributable to fire. This kerosene we are using is an explosive only when under high pressure. In the petrol tank it's safe; even in the carburetter it is non-explosive; but directly it enters the cylinders and is affected by the compression-stroke it is not only more volatile, but far more powerful than the best aviation spirit." "But I take it that the fuel in the 'bus is under pressure," remarked Peter, who was beginning to take a lively interest. "It must be, in order to maintain an even feed to the motor." "You're wrong there," replied his relative. "I'll explain that when I show you a flying-boat ready for service." An inspection of the assembling sheds where aircraft were in various states of completion followed, Uncle Brian pointing out various "gadgets" embodied in the design to render the machine practically "fool-proof". "Now, here's a flying-boat in an advanced stage," he said. "All that is required to complete her is painting and varnishing. That's done in another building. What do you think of this little fellow?" The "little fellow" was actually one hundred and twenty feet in length, with a wing-span of a little over sixty feet. With the exception of the patent glass scuttles and screens it was constructed entirely of metal. "There you are," continued the inventor. "A child could fly it once it has 'taken off'. The planes, you see, are on a horizontal axis, and automatically arranged so that should the diving angle become too acute they will adjust themselves and bring the 'bus into a position of safety. The horizontal rudders, too, can either be controlled by hand or set to act automatically. Thus a pilot can set a course and the machine will just carry on, even to the extent of allowing for 'drift' and unequal wind pressure. Get aboard, Peter; I want to show you the motors."