The following day the first box of material arrived from Kansas City, and was taken to Mr. Giles' machine shop, which, having formerly been the army stables, was a great deal larger than was needed for the machinist's work, and he was able to give Hawke and the boys a roomy space at the rear.
A box from Denver came on Monday morning, and in the afternoon there was a consignment from New York. The engine was to be sent by freight from Fort Omaha, and would take some time to reach Silver City, but, as Hawke explained, it was the last thing to be used and the delay would not matter.
By Wednesday morning, therefore, which was the day after the Fourth, all was ready to go ahead on the aeroplane. The Fourth had been unusually quiet for the boys because Herb could not take part in any active festivities. While his injury had been slight, and was now practically healed, his father insisted that he should remain perfectly quiet and not become excited by unwarranted celebration. This was a hardship for so active a boy as Herb, but to please his father he obeyed without complaint.
As reparation, the rancher ordered a lavish display of fireworks from Albuquerque, and in the evening the boys were entertained by an exhibition that was worthy of young princes.
The exhilaration which followed this event, their sympathy for Herb, the gratitude they felt for the generous rancher, and their eagerness to solve the mystery of the Bread Pudding ranch, which was heightened by the incidents of the last few weeks, coupled with their growing interest in aviation, gave the boys an enthusiasm for the work of constructing the biplane which guaranteed success.
Hawke set up his model in the shop for their guidance, and, desiring to start them with fundamentals, he dissected the wing of a hawk, and, the first thing Wednesday morning, explained to them the first principles of plane construction, using the formation of the wing as an illustration.
"The early planes were straight," he explained, "but we have since learned that the curved surfaces are far more efficient. Keep in mind the idea of the bird, the shape of his wings, and you have the best working basis for building a plane." The aviator believed, with some other specialists, that examples taken from nature were the best sort of instruction for the novice.
The materials were unpacked, including all necessary tools, and without wasting much time on preliminaries, the boys set heartily to work.
"I am planning to equip this machine with swinging wing ends," said Hawke. "This is something not used on many biplanes, but it will be necessary to have them if we are to follow the maneuvers of a bird. If the wing tips are made with a down curve at their ends, the result of swinging them to the rear will be to increase the lifting power, while at the same time reducing the resistance of the air to forward movement. This would afford an ideal method of steering, being exactly like that employed by birds."
Later, when work was begun on these wing tips, the boys fully understood Hawke's theory.