rbour in 1819 I found so many errors in the
bearings that were taken as induced me to suspect an original error, and
on this occasion a very considerable one was detected.
When Captain Flinders passed round Van Diemen's Land in the Norfolk he
obtained a meridional supplementary altitude of the sun to the south, his
vessel being under the land, which made the South-west Cape in 43 degrees
29 minutes South; but finding the next day that his instrument was 2
minutes 40 seconds in error to the north he assigned to the cape a
position of 43 degrees 32 minutes. In the Introduction to his voyage* he
makes some remarks in a note upon the positions assigned to it by
Captains Cook and Furneaux; the latter officer placed it in 43 degrees 39
minutes, in which I also found it to be by its transient bearing from the
South Cape. By a series of bearings carried along the coast its position
is thirty-three miles West 3 degrees South true, from the South Cape.
(*Footnote. Flinders volume 1 Introduction page 179.)
All parts of the coast in this interval are proportionally in error as to
latitude but tolerably well placed in reference to the coast. The
subjoined are the positions now assigned to the following places, namely:
COLUMN 1: NAME OF PLACE.
COLUMN 2: LATITUDE.
COLUMN 3: LONGITUDE ACCORDING TO CAPTAIN FLINDERS' SURVEY.
South Cape : 43 degrees 38 minutes : 146 degrees 56 minutes.
Mewstone : 43 degrees 46 minutes : 146 degrees 31 1/2 minutes.
South-west Cape : 43 degrees 39 minutes : 146 degrees 12 minutes.
The south-east cape of Bruny Island, Tasman's Head, is also placed too
much to the southward in Captain Flinders' chart as well as in that of
Baudin. From the Mermaid it was set in a line with the south-east cape on
the bearing of North 56 degrees East (the vessel's head being to the
eastward); and on this occasion (the brig's head being to the westward)
it bore, when in the same line, North 53 degrees East. The variation in
the latter case was 9 degrees East, but in the former no more than 6
degrees was allowed, and Captain Flinders found even 4 degrees
sufficient.
I passed outside the Mewstone and took its bearing as it came on with the
points of the land between the south-west and the south-east capes, by
which I satisfied myself beyond a doubt of the correctness of my
observations and of the error into which Captain Flinders had fallen, and
which must either be attributed to the imperfection of his instrument
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