The colonel was most enthusiastic and congratulated them heartily, but the two lieutenants kept in the background and offered no comments. “There are only a few wires to tighten a little,” Stanley informed the commanding officer. “They are always liable to slacken somewhat during the first flights. The fuselage is lined up perfectly. If the colonel so desires, we shall be glad to make a long cross-country flight next Sunday. That could serve as a final test, after which the ship would be ready to go into commission for the regular work of training cadets.” “Splendid!” the colonel replied. “Go anywhere you like. Give the machine a most thorough trial. The instructors and pupils are waiting impatiently for their turn.” Two days later, as they were going over the ship for a final inspection, Stanley suddenly noticed that the keys had been removed from the pins that fastened the right upper wing to the body. With a slight motion of his hand he indicated the fact to Ted. “Now we shall find out who is responsible for that,” he said to Ted between his teeth. They had the ship rolled out on the line and started the engines. The colonel and the two lieutenants were on the field as usual, watching the operations. “Perhaps the lieutenants would like a flight to-day?” Stanley suggested pleasantly, approaching the trio. “With the colonel’s consent, and so far as we are concerned, the ship is at your disposal.” The two began to look uncomfortable, and one of them stammered an excuse about not being prepared with the proper clothing. The colonel promptly suggested that they might use the outfits of the Americans if they desired, but upon this the other one pleaded illness. “Well,” Stanley said, looking straight at the two, “we thought we might go up for a few minutes, but I guess we had better not. If it is not safe for you, it is not safe for us.” The colonel understood that there was some difficulty, but said nothing until the two instructors had gone. Then he questioned the Americans as to the meaning of the affair. They showed him the pins with the missing keys. “But you have no evidence against any one!” he said slowly. “This is most serious, but I cannot accuse any one of such an act without proof.” “No, but in the future the hangars must be guarded day and night. No one must be permitted to enter without a written pass from you.” “That is a good idea. It shall be done. I shall immediately issue an order to that effect.” The damage was soon repaired and the ship rolled back into the hangar. Ted spent the greater part of the next morning making purchases in the city, and the packages were delivered to the field early in the afternoon. They had been compelled to buy numerous things connected with their work during the previous weeks, so the arrival of the boxes caused no comment. Ted stored them in a corner of the hangar and covered them with a tarpauling.