immensity.

The name, ``coal-sacks,'' given to these strange voids is hardly
descriptive. Rather they produce upon the mind the effect of blank
windows in a lonely house on a pitch-dark night, which, when looked at
from the brilliant interior, become appalling in their rayless murk.
Infinity seems to acquire a new meaning in the presence of these black
openings in the sky, for as one continues to gaze it loses its purely
metaphysical quality and becomes a kind of entity, like the ocean. The
observer is conscious that he can actually see the beginning of its
ebon depths, in which the visible universe appears to float like an
enchanted island, resplendent within with lights and life and gorgeous
spectacles, and encircled with screens of crowded stars, but with its
dazzling vistas ending at the fathomless sea of pure darkness which
encloses all.

The Galaxy, or Milky Way, surrounds the borders of our island in space
like a stellar garland, and when openings appear in it they are, by
contrast, far more impressive than the general darkness of the
interstellar expanse seen in other directions. Yet even that expanse
is not everywhere equally dark, for it contains gloomy deeps
discernable with careful watching. Here, too, contrast plays an
important part, though less striking than within the galactic region.
Some of Sir William Herschel's observations appear to indicate an
association between these tenebrious spots and neighboring star clouds
and nebulæ. It is an illuminating bit of astronomical history that
when he was sweeping the then virgin heavens with his great telescopes
he was accustomed to say to his sister who, note-book in hand, waited
at his side to take down his words, fresh with the inspiration of
discovery: ``Prepare to write; the nebulæ are coming; here space is