stock had died, there was less vitality than at first; especially each
morning, after seven or eight hours unaided by aeration.

Tired of what seemed an ineffectual struggle, I determined to leave the
Aquarium untouched for a day, and await the result. Accordingly, the
charcoal was withdrawn and aeration discontinued. The milky cloud
increased in density, and the whole mass of water became turbid. The
fishes kept constantly near the surface, swam languidly, and snatched
mouthfuls of atmospheric air. The Eel became bloodshot about the gills,
and, writhing, gasped for breath. The Soldier-Crabs hung listlessly
from their shells, and no longer went about in quest of food. Even the
Actinise shrunk to half their former size; and the Buccina, crawling
above the water, ranged themselves in a row upon the dry glass.

Disappointed, but not discouraged, I filled several shallow pans with
pure sea-water, clean sand, and fresh plants, and transferred to them my
suffering and wellnigh exhausted animals. A day restored them to their
normal condition, and now I was ready to begin my Aquarium anew.

But to what purpose should I begin anew? Would there not be the same
failure? What had been wrong?

At least two great faults were evident. First, in order to guard against
the possibility of a leak, the bottom and posts of the tank had been
covered with many coats of an alcoholic varnish. Now it was probable
that time enough had not elapsed between the several applications for
the thorough evaporation of the alcohol. Might not its gradual infusion
in the water have caused the death of the animalcula in such numbers as
to taint the whole by their decay?