"Hello!—it looks like some kind of building—completely black—quite hard to see. No windows or any other features. Just a big, vertical slab—it must be at least a mile high to be visible from this distance. It reminds me—of course! It's just like the thing you found on the moon! This is TMA-1's big brother!"
He was heading straight towards the huge, dark mass that soared in such geometrical perfection above the featureless plain. It was a blank as the flat white beneath surface; until now, he had not appreciated how enormous it really was. There were very few buildings on Earth as large as this. And as far as could be judged, its proportions were precisely the same as TMA-1's—that curious ratio 1 to 4 to 9.
And then you waited, marshalling your thoughts and brooding over your untested powers. For though you are master of your Rack, you are not quite sure what to do next.
But you will think of something.