Two sorts of boats are employed for this purpose; one is of about thirty tons burden, the other much smaller. They use a number of nets called a set, about twenty in all, joined together. Each net is about 170 feet long, and 40 deep. United lengthways they form a wall three-quarters of a mile long, the lower part kept down by leads, the upper floated on the surface by corks. Sometimes they are even much longer.
Within the meshes of this net the fish, as they swim rapidly forward, entangle themselves. They easily get their heads through, but cannot withdraw them, as they are held by the gills, which open in the water like the barbs of an arrow. Their bodies also being larger than the meshes, they thus remain hanging, unable to extricate themselves.
The driving-boat is made fast to one end of the wall, where she hangs on till the time for hauling the net arrives.
The fishermen prefer a thick foggy night and a loppy sea, as under those circumstances the pilchards do not perceive the net in their way. At times, however, when the water is phosphorescent, the creatures which form the luminous appearance cover the meshes so that the whole net becomes lighted up.
This is called “briming,” and the pilchards, thus perceiving the trap in their way, turn aside and escape its meshes.
As briming rarely occurs during twilight, and the ocean is at that time dark enough to hide the wall of twine, the fishermen generally shoot their nets soon after sunset and just before dawn, when the fine weather makes it probable that they will be lighted up by the dreaded briming at the other hours of the night.
The operation of hauling in nearly a mile of net, with its meshes full of fish, is an arduous task, especially during a dark night, when the boat is tossed about by a heavy sea, and at no time indeed can it be an easy one. The hardy fishermen pursue this species of fishing during the greater part of the year, for small schools of pilchards arrive in the Channel as early as the month of May, and remain far into the winter, till the water becomes too cool for their constitutions, when they return eastwards to seek a warmer climate in the depths of the Atlantic, or swim off to some unknown region, where they may deposit their spawn or obtain the food on which they exist. Little, however, is known of the causes which guide their movements, and the Cornish fishermen remain satisfied by knowing the fact that the beautiful little fish which enables them to support themselves and their families are sent annually by their benignant Creator to visit their coasts, and seldom trouble themselves to make any further inquiries on the subject.