as the walls of the tower decrease in thickness as they rise, the
several apartments necessarily increase as they ascend.

The second floor is reached by a wooden staircase or ladder, leading up
through a "manhole" in the ceiling. Here is the lightroom store, which
contains large tanks of polished metal for the oil consumed by the
lights. A whole year's stock of oil, or about 1100 gallons, is stored
in these tanks. Here also is a small carpenter's bench and tool-box,
besides an endless variety of odds and ends,--such as paint-pots,
brushes, flags, waste for cleaning the reflectors, etcetera, etcetera.

Another stair, similar to the first, leads to the third floor, which is
the kitchen of the building. It stands about sixty-six feet above the
foundation. We shall have occasion to describe it and the rooms above
presently. Meanwhile, let it suffice to say, that the fourth floor
contains the men's sleeping-berths, of which there are six, although
three men is the usual complement on the rock. The fifth floor is the
library, and above that is the lantern; the whole building, from base to
summit, being 115 feet high.

At the time when Ruby entered the door of the Bell Rock Lighthouse, as
already described, there were three keepers in the building, one of whom
was on his watch in the lantern, while the other two were in the
kitchen.

These men were all old friends. The man in the lantern was George
Forsyth, who had been appointed one of the light-keepers in
consideration of his good services and steadiness. He was seated
reading at a small desk. Close above him was the blazing series of
lights, which revolved slowly and steadily by means of machinery, moved
by a heavy weight. A small bell was struck slowly but regularly by the
same machinery, in token that all was going on well. If that bell had
ceased to sound, Forsyth would at once have leaped up to ascertain what
was wrong with the lights. So long as it continued to ring he knew that
all was well, and that he might continue his studies peacefully--not
quietly, however, for, besides the rush of wind against the thick
plate-glass of the lantern, there was the never-ceasing roar of the
ventilator, in which the heated air from within and the cold air from
without met and kept up a terrific war. Keepers get used to that sound,
however, and do not mind it.

Each keeper's duty was to watch for three successive hours in the
lantern.

Not less familiar were the