a swivel-joint. To this the dragging rope is bent, which must be three
times as long, in dredging, as the depth of the water. This is fastened
to the stern of a boat under sail, and thus the bottom is raked of
all sorts of objects; among which, on emptying the net, many living
creatures for the aquarium are found. These may be placed temporarily in
jars; though plants, mollusks, Crustacea and Actiniae may be kept and
transmitted long distances packed in layers of moist sea-weed.

For all this detail, labor, and patient care, we may reasonably find
two great objects: first, the cultivation and advancement of natural
science; second, the purest delight and healthiest amusement.

In the aquarium we have a most convenient field for the study of
Natural History: to learn the varieties, nature, names, habits, and
peculiarities of those endless forms of animated existence which dwell
in the hidden depths of the sea, and at the same time to improve our
minds by cultivating our powers of observation.

The pleasure derived from the aquarium comes from the excitement of
finding and collecting specimens, as well as from watching the tank
itself. There can be no more pleasant accompaniment to the sea-side walk
of the casual visitor or summer resident of a watering-place, than to
search for marine plants and animals among the fissures, rocks, and
tide-pools of the sea-washed beach or cape.

Nature is always as varied as beautiful. Thousands of strange forms
sport under the shadow of the brown, waving sea-weeds, or among the
delicate scarlet fronds of the dulse, which is found growing in the
little ponds that the inequalities of the beach have retained. It is
down among the great boulders which the Atlantic piles upon our coast,