like heavy
hail.... The men, however, were not perturbed. Sleeping, even under such
conditions, was far preferable to doubtful rest in a bunk upon an
attendant vessel, rolling and pitching with the motion of the sea. They
had had a surfeit of such experience ... while the barrack was under
erection.

"For two years it withstood the seas without incident, and the engineer
and men came to regard the eyrie as safe as a house on shore. But one
night the little colony received a shock. The angry Atlantic got one or
two of its trip-hammer blows well home, and smashed the structure to
fragments. Fortunately, at the time it was untenanted."

No time was lost in rebuilding the barrack and this time it withstood
all tests until it was torn down after Skerryvore was finished.

"While the foundations were being prepared, and until the barrack was
constructed, the men ran other terrible risks every morning and night
landing upon and leaving the polished surface of the reef. Five months
during the summer was the working season, but even then many days and
weeks were often lost owing to the swell being too great to permit the
rowing boat to come alongside. The engineer relates that the work was 'a
good lesson in the school of patience,' because the delays were frequent
and galling, while every storm which got up and expended its rage upon
the reef left its mark indelibly among the engineer's stock in trade.
Cranes and other materials were swept away as if they were corks;
lashings, no matter how strong, were snapped like pack-threads.

"Probably the worst experience was when the men on the rock were
weather-bound for seven weeks during one season.... Their provisions
sank to a very low level, they ran short of fuel, their sodden clothing
was worn to rags....

"Six years were occupied in the completion of the work, and, as may be
imagined, the final touches were welcomed with thankfulness by those who
had been concerned in the enterprise."

It was in meteorological researches and illumination of lighthouses,
however, that Thomas Stevenson did his greatest work. It was he who
brought to perfection the revolving light now so generally used.

In spite of this and other valuable inventions his name has remained
little known, owing to the fact that none of his inventions were ever
patented. The Stevensons believed that, holding government appointments,
any original work they did belonged to the nation. "A patent not only
brings in