18 
GREENLAND VOYAGE. 
vivid coruscations. Ursa Major was at one time 
encircled with such a characteristic blazonry of 
light, that the Bear seemed to spring into figure, 
and to be shaking his shaggy limbs, as if in con¬ 
tempt of the less distinguished constellations 
around him. The Pleiades were almost obscured 
by the light produced by the aurora ; though Ve¬ 
nus, and all the superior stars, shone with be¬ 
coming splendour. I have never been sensible 
that the shooting of the aurora was accompanied 
by any noise: the turbulence, indeed, of the water 
at sea, or noise of the sails during calms, prevents 
slight sounds from being heard. 
For some days after the aurora borealis, the 
weather was uncommonly fine. The wind wa 9 
generally moderate, with frequent calms. During 
a run of fifty leagues, the sea was constantly of 
an olive-green colour, remarkably turbid; but in 
the afternoon of the 17th of April, it changed to 
transparent blue. The green appearance of the 
sea in these latitudes, I formerly ascertained to be 
occasioned by an innumerable quantity of small 
molluscous animals, of a yellowish colour, contained 
in it. A calculation of the number of these animals 
in a space of two miles square, and 250 fathoms 
deep, gave an amount of 23,888,000,000,000 *. 
* Accouqt of the Arctic Regions, vol. i, p. 179 . 
