CRUISE OF THE ALERT.’
INTRODUCTION.
IN the summer of 1878 it was decided by the Lords of the
Admiralty to equip a vessel for the threefold purpose of
continuing the survey of the Straits of Magellan, of investigating
the nature and exact position of certain doubtful reefs and islands
in the South Pacific Ocean, and of surveying a portion of the
northern and western coasts of Australia. The special object of
the Magellan portion of the work was to make such a detailed
survey of the sheltered channels extending southward from the
Gulf of Peñas to Port Tamar as would enable vessels to pass
from the Straits to the Pacific, and vice versa, without having to
encounter the wild and inhospitable outer coasts presented by the
chain of desolate islands here fringing the western coasts of South
America. It was also desirable that additional anchorages should
be found and surveyed, where vessels might lie in safety while
waiting for the cessation of a gale, or for a favourable tide to help
them through the straits. The surveys made by the Adventitre
and Beagle in 1826-36, and by the Nassau in 1866-9, were
excellent so far as they went, and so far as the requirements of
their times were concerned ; but the great increase of ocean
navigation within the last few years had rendered it necessary
that the charts should contain more minute surveys of certain
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