At about every other flight they passed a window; each window showed them a pale and tragic dawn lifting itself laboriously over London.

From each the innumerable roofs of slate looked like the leaden surges of a grey, troubled sea after rain.

Syme was increasingly conscious that his new adventure had somehow a quality of cold sanity worse than the wild adventures of the past.

Last night, for instance, the tall tenements had seemed to him like a tower in a dream.
As he now went up the weary and perpetual steps, he was daunted and bewildered by their almost infinite series.

But it was not the hot horror of a dream or of anything that might be exaggeration or delusion.
Their infinity was more like the empty infinity of arithmetic, something unthinkable, yet necessary to thought.