Good service was done to the cause of science when, some fifteen or
twenty years since, Robert Ball of Dublin invented the naturalist’s
dredge. A huge unwieldy form of the implement has indeed been long in
use among fishermen for the obtaining of oysters and scallops; a clumsy
affair, of which the frame, furnished only with a single lip, was four
or five feet wide, and the bag was formed of iron rings, two inches in
diameter,--a loose and open sort of chain-mail. There was an object in
this last arrangement; for while the chain-work retained all oysters
of a marketable size, the meshes allowed all to escape which were of
less dimensions, and so these remained on the ground to grow bigger for
another season.
Naturalists did gladly avail themselves of this uncouth apparatus, and
many valuable things were scraped from the sea-bottom thereby; but
they never could have used it without regret at the thought of the
thousands of unknown and unimagined treasures which must have slipped
through those huge meshes. No object of less size than two inches in
any diameter had a chance of being brought to the surface; and how many
precious specimens range below these dimensions we are now beginning to
discover.
Yes; I’m glad I have got a Ball’s dredge; and this fair autumnal
morning I mean to use it; to go out with honest Harvey, and scrape the
stony sea-bottom in the offing yonder. It is a nice portable affair,
that one hand can manage; eighteen inches by four and a half are the
dimensions of the frame; the scraping lips are double, one on each
edge, so that, however the dredge falls on the bottom, it is sure to
scrape; a double bridle from each side meets in a ring to which the
rope is made fast; and the bag, some twenty inches deep, is made of
stout twine, well netted, with meshes about half an inch in diameter.
Owing to the swelling of the twine in the water, there is scarcely
anything of value that will escape such a net.
Harvey has carried down everything to Babbicombe Beach, and now all is
on board; dredge, sieve, pans, buckets, jars, bottles, _ad libitum_.
And now we run up the mainsail and jib, and with a light westerly
breeze and smooth water, lie up for Exmouth, or a little beyond, for
about an hour.