220 THE OLD RED SANDSTONE. 
deposit of full ninety feet had overlain the conglomerate, the 
depth became still more profound than at first. A fine, semi- 
calcareous, semi-aluminous deposition took place in waters 
perfectly undisturbed. And here we first find proof that 
this ancient ocean literally swarmed with life—that its 
bottom was covered with miniature forests of alge, and its 
waters darkened by immense shoals of fish. 
In middle autumn, at the close of the herring season, when 
the fish have just spawned, and the congregated masses are 
breaking up on shallow and skerry, and dispersing by myri- 
ads over the deeper seas, they rise at times to the surface by 
a movement so simultaneous, that for miles and miles afound 
the skiff of the fisherman nothing may be seen but the bright 
glitter of scales, as if the entire face of the deep were a blue 
robe spangled with silver. I have watched them at sunrise 
at such seasons on the middle of the Moray Frith, when, far 
as the eye could reach, the surface has been ruffled by the 
splash of fins, as if a light breeze swept over it, and the red 
light has flashed in gleams of an instant on the millions and 
‘tens of millions that were leaping around me, a handbreadth 
into the air, thick as hail-stones in a thunder-shower. The 
amazing amount of life which the scene included, has im- 
parted to it an indescribable interest. On most occasions the 
inhabitants of ocean are seen but by scores and hundreds ; 
for in looking down into their green twilight haunts, we find 
the view bounded by a few yards, or at most a few fathoms ; 
and we can but calculate on the unseen myriads of the sur- 
rounding expanse by the seen few that occupy the narrow 
space visible. Here, however, it was not the few, but the 
myriads, that were seen—the innumerable and inconceiva- 
ble whole —all palpable to the sight as a flock on a hill-side ; 
or, at least, if all was not palpable, it was only because sense 
