I was about to turn again to the interesting work of observation through the lens in the floor, when my attention was diverted by the sight of something like a whitish cloud visible through the upper window on my left hand.
Examined by the telescope, its widest diameter might be at most ten degrees.

It was faintly luminous, presenting an appearance very closely resembling that of a star cluster or nebula just beyond the power of resolution.

As in many nebulae, there was a visible concentration in one part; but this did not occupy the centre, but a position more resembling that of the nucleus of a small tailless comet.

The cloudlet might be a distant comet, it might be a less distant body of meteors clustering densely in some particular part of their orbit; and, unfortunately, I was not likely to solve the problem.

Gradually the nebula changed its position, but not its form, seeming to move downwards and towards the stern of my vessel, as if I were passing it without approaching nearer.