To the coral-fishers of the Mediterranean, who seek the precious red
coral, which grows firmly fixed to rocks at a depth of sixty to eighty
fathoms, both the dredge and the trawl would be useless. They, therefore,
have recourse to a sort of frame, to which are fastened long bundles of
loosely netted hempen cord, and which is lowered by a rope to the depth
at which the hempen cords can sweep over the surface of the rocks and
break off the coral, which is brought up entangled in the cords. A
similar contrivance has arisen out of the necessities of deep-sea
exploration.

In the course of the dredging of the _Porcupine_, it was frequently found
that, while few objects of interest were brought up within the dredge,
many living creatures came up sticking to the outside of the dredge-bag,
and even to the first few fathoms of the dredge-rope. The mouth of the
dredge doubtless rapidly filled with mud, and thus the things it should
have brought up were shut out. To remedy this inconvenience Captain
Calver devised an arrangement not unlike that employed by the coral-
fishers. He fastened half a dozen swabs, such as are used for drying
decks, to the dredge. A swab is something like what a birch-broom would
be if its twigs were made of long, coarse, hempen yarns. These dragged
along after the dredge over the surface of the mud, and entangled the
creatures living there--multitudes of which, twisted up in the strands of
the swabs, were brought to the surface with the dredge. A further
improvement was made by attaching a long iron bar to the bottom of the
dredge bag, and fastening large bunches of teased-out hemp to the end of
this bar. These "tangles" bring up immense quantities of such animals as
have long arms, or spines, or prominences which readily become caught in
the hemp, but they are very destructive to the fragile organisms which
they imprison; and, now that the trawl can be successfully worked at the
greatest depths, it may be expected to supersede them; at least, wherever