expunge them, it becomes a serious duty to traverse their position in
every possible direction. Should the weather be favourable, it would be
desirable, while crossing their parallel, to obtain one very deep cast of
the lead, and should that succeed in reaching the bottom, the sacrifice
of a few days will be well bestowed in endeavouring to trace a further
portion of the bank. A small chart, showing the tracks of various ships
across this place, is hereto annexed, and as the meridian of 16 degrees
22 minutes nearly bisects the two adjacent courses, you are recommended
to cross their parallel in that longitude.

From the Canary Islands to the coast of Brazil, and indeed throughout
every part of your voyage, you should endeavour to pass over the places
of all the reported Vigias which lie near your course, either outward or
homeward. You will perceive a multitude of them carelessly marked on
every chart, but of some you will find a circumstantial description in
that useful publication, the Nautical Magazine, and a day devoted to the
search of any, which will not withdraw you too far from your due course,
will be well employed.

The rocks off Cape Leeuwin, some near King George Sound, the dangerous
patch off Kangaroo Island, and many others, of which accounts are given
in the above work, ought, if possible, to be examined, as more
immediately appertaining to your own field. Whenever found, the depth,
nature, and limits of the banks on which they stand, should be
determined, as they might prove to be of sufficient extent to give
warning to the danger, and then a direct course should be immediately
made by the Beagle to the nearest land, where a convenient place should
be selected, and its position carefully ascertained.

At Swan River you will have previously learnt from Lieutenant Roe, the