"Warm up the model," I said. My voice had a thin, windy sound and I couldn't keep it steady. "From the way they're flitting around that bubble they've got troubles of their own—and they're going to have more!"

Dora understood then what I had in mind. "Their generator is weakening the barrier to the dimension above this one!" she said. "Jerry, something is trying to break through, isn't it?"

Our little Di-tube model gave a tentative sizzle, and it sounded pitifully weak. Using it was like tackling a grizzly with a hatpin—but there was no help for that now.

"They aren't zipping around that space-blister for exercise," I said. "Maybe they don't know exactly what is on the other side, but they're worried."

That was the whole crazy million-to-one chance that had brought me there. It stood to reason that the Blazers' Di-tube generator would create a strain-warp similar to ours in their own dimension. If we could puncture their weak spot as they had punctured ours....


The two-inch beam of our little Di-tube shot out, boring wide of the outlandish blob that was the Blazers' generator. I swung it back, correcting my aim, and the heat went on.

The Blazers dropped their work instantly and whirled up toward us. But for once they were slow—our little Di-shaft sliced through and beyond them. And touched the strain-bubble.

There was a searing flash and a soundless jarring concussion, and the thing went up in a blinding shower of orange sparks.

It was over as quickly as that. The Blazers swarming toward us whipped back to man the breach we had made and they had unexpected reenforcements—they must have alerted their party on Earth already because the wavering Di-tube was suddenly crowded with returning fire-worms, zipping back home to superspace.