"It did! It ate some, Lea! Watch it now!"
The fly was standing motionless. For a breathless instant fear stabbed into Carter. Suppose this were the enlarging drug, the same as the other save a different color. That fly, getting large, might dart away. In a moment it might be too large to kill. Still growing, it would burst the room, wreck the house.... With the flash of terrified thoughts, Carter raised his hand to try and kill the motionless insect. But he stopped.
"Look! It is smaller!" Lea murmured.
With wings still folded it was crawling in a wavering little circle near the pellet. And visibly it was diminishing in size. Already the tiny pellet seemed gigantic beside it. Silently Lea and Carter stared. The fly was a tiny black midge now, swiftly crawling, but moving so slowly on the polished tabletop.
"Can you still see it, Lea?" Carter blinked; bent down. It seemed that the insect already was beyond his sight.
"Yes. I see it."
And then it had vanished. Not gone. They knew it was still there; dwindling; soon it would be beyond the reach of any microscope....
For a moment, in the silent little bedroom, Carter and the girl stared at each other, overwhelmed by the momentousness of their discovery.
"You want to go back to your own world, Lea?" he murmured at last. "You can do it now—with this."
"Yes—yes! That is what I shall do." Her eyes were shining. Her whole little figure was trembling. Swiftly she gathered up the pellets, replaced them in the vial. "Your father shall have no chance to destroy them," she declared defiantly. "They are mine, not his."