“I want to try a little experiment,” Tom replied as he took down the thermometer.
Bud knocked and the guard opened the door. When it became evident that he did not understand English, Bud went through the motions of drinking. The man obliged with a bottle of water, and then barred the door again.
Tom climbed onto Bud’s shoulders again, but this time at the rear window.
The young inventor broke the thermometer tube and let the mercury drip against various sections of the aluminum frame. Bud watched in fascinated silence. “This mercury ought to cut through the oxide surface on the aluminum,” Tom explained. “Now for the water.”
Bud handed up the bottle and slowly Tom poured the water on to the place where the mercury drops had fallen. The aluminum began to dissolve. After several applications, the chemical had eaten through the frame.
82 TOM SWIFT AND HIS ROCKET SHIP
“Pst!” he signaled. “I’ve done it!”
“Honestly? Now what?” Bud asked.
“As soon as I pull these bars out, we’re going to get away in that cargo plane!”
“How about the guard?” Bud asked as Tom easily pulled out the bars.
“We’ll take care of him. Come on!”
Bud followed Tom through the window and dropped to the ground.
“I’ll duck behind that big bush,” Tom whispered. “You make a scraping sound to attract the guard. When he comes around here to investigate, jump him. I’ll open the door and we’ll lock him in.”
When Tom was well hidden about ten feet from the building, Bud broke off a branch and swished it around on the ground. The guard heard the sound and came on a run. Soon he rounded the corner, muttering to himself.