He advanced to the cannon-like device at the other end of the room, swung it on its swivel till it was pointing directly at that fluorescent orange tube on the table.
“Watch closely!” he said, throwing a switch.
There was a sudden, whining hum in the air and the nib of the big tube glowed a soft, velvety green. Jim gazed at the scene with rapt attention.
“Don’t look at that one!” whispered Joan. “Look at the other!”
Jim did so, and saw that its fluorescence was waning.
A moment more the professor held the current on, while the tube grew white. Then he threw off the switch.
“Now let us have a look at our captive,” he said, striding over.
They followed, and one glance told Jim what had happened. That sinister lump of orange metal had vanished.
But where was it? That was what he wanted to know.