"No, I'll wait here."

Maskull immediately began the ascent. Hardly had he mounted half a
dozen steps, however, before he was compelled to pause, to gain
breath. He seemed to be carrying upstairs not one Maskull, but
three. As he proceeded, the sensation of crushing weight, so far
from diminishing, grew worse and worse. It was nearly physically
impossible to go on; his lungs could not take in enough oxygen, while
his heart thumped like a ship's engine. Sweat coursed down his face.
At the twentieth step he completed the first revolution of the tower
and came face to face with the first window, which was set in a high
embrasure.

Realising that he could go no higher, he struck another match, and
climbed into the embrasure, in order that he might at all events see
something from the tower. The flame died, and he stared through the
window at the stars. Then, to his astonishment, he discovered that it
was not a window at all but a lens.... The sky was not a wide
expanse of space containing a multitude of stars, but a blurred
darkness, focused only in one part, where two very bright stars, like
small moons in size, appeared in close conjunction; and near them a
more minute planetary object, as brilliant as Venus and with an
observable disk. One of the suns shone with a glaring white light;
the other was a weird and awful blue. Their light, though almost
solar in intensity, did not illuminate the interior of the tower.

Maskull knew at once that the system of spheres at which he was
gazing was what is known to astronomy as the star Arcturus.... He
had seen the sight before, through Krag's glass, but then the scale