I flipped the switch on the three-foot bakelite cabinet that housed our little Di-tube generator. It sizzled for a moment with a sound like frying bacon and shot out a two-inch beam from the copper helix at the bottom—a beam as clearly outlined as a water pipe but which couldn't really be seen because there was nothing there.
Don't let that throw you. Just take my word for it—it was a two-inch cylinder of nothing at all, a clean-cut shaft of absolute vacancy.
Until you looked into the twin-prism eyepiece we had rigged up, that is. You couldn't sight directly down the tube itself because the generator's energy feedback raised a glowing force-bubble that hung above the cabinet like a basketball-sized neon bulb. That bubble represented a spherical strain against superspace, so Doc said, in compensation for the forced passage of the Di-tube through the continuum of subspace. A demonstration of the first law of physics, to every action an equal and opposite reaction.
Three-star Corbin looked first, pulling his rank. One glimpse of the Twisters was enough—he jumped a foot and turned the color of a dead flounder.
"In God's name," he choked when he got his breath back, "what are they?"
"We don't know," I told him. "But I'll give you odds that they wouldn't be chummy if they ever got up here."
I knew how he felt. My first sight of the Twisters had given me nightmares for a week. I won't try to describe them because they never looked alike to any two people. Doc said that a description didn't matter because what we thought we saw were only multidimensional cross-sections anyway—but I wouldn't know about that. To me they looked like inside-out octopuses.
"You see?" Doc snapped, bristling his beard triumphantly. "The cross-sections we see of these inhabitants of subspace give no clue whatever as to their true nature. Even you should realise that opening a larger rift into their domain would be an extremely dangerous undertaking."
"Allied Military," said Three-star Corbin, who had got some of his color back, "is quite capable of dealing with these brutes if necessary. Dr. Maxey, you will proceed with the construction of a full-scale Dimension-tunnel."
The doc made some sulphurous remarks that were lost in his beard.