The heavens are dark as midnight:—no star or planet penetrates the gloom with a friendly ray:—yet the color of the overhanging vault is by no means uniform. Broad tracts or patches of intense obscurity cover the chief part of the field of view; but, at intervals, you may perceive long, moving, dusky lines dividing these heavy masses, made visible by a strange and unaccountable half illumination. As they sweep hurriedly by, on their northward course, seemingly almost within reach from the mast head, we are made painfully conscious that the wings of the tempest are hovering over us in dangerous proximity. Except the lamps in the binnacle, there is no obvious source of light above or around us: yet the outlines of the vessel, with all the labyrinth of spars and rigging, are dimly traceable in the murky air. Whence do we derive this power of vision? you will naturally inquire.—A glance at the surface of the water will explain it. Every wave, as it combs and breaks, bears on its summit a high crest of foam, visible at a great distance by its own moonlight, or soft silvery radiation. Each little ripple carries its tiny lantern. Wherever the sea is disturbed by the motion of the vessel, and especially at the bow, where the waters are rudely disparted, or in the wake, where they rush together violently as she shoots along, a gentle, milky light is broadly diffused; and here and there a brilliant spark is seen beneath the surface shining distinct and permanent, like a star submerged, or gleaming and disappearing alternately, like the fire-flies of June. The phosphorescence of the sea is unusually feeble at present, but it is sufficient to prevent a total darkness, and by its aid we trace the dim forms of surrounding objects, while a slight reflection from the clouds betrays the threatening aspect of the weather.