The coveted shell-fish, in most instances, preferred tolerably deep water; and to procure them in any quantity it was necessary that they should be fished up from a depth of some fathoms.

The mode in which they were captured was the following.

A long rope was let down into the sea, with baskets of reeds or rushes attached to it at intervals, constructed like our lobster-traps or eel-baskets, with an opening that yielded easily to pressure from the outside, but resisted pressure from the inside, and made escape, when once the trap was entered, impossible.

The baskets were baited with mussels or frogs, both of which had great attractions for the _Purpurae_, and were seized and devoured with avidity.

At the upper end of the rope was attached to a large piece of cork, which, even when the baskets were full, could not be drawn under water.