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miinitia; of whatever knowledge has been acquired, will bt>
dociunents of far greater value in this office, to be reduced or
referred to, than highly finished plmis, where accuracy is often
sacrificed to beauty.
“ This applies particularly to the hills, which iii general cost
so much labour, and are so often put in from fancy or froin
memory after the lapse of mouths, il not of } ears, instea o
being projected while fresh in the mind, or while any mcon-
sistencies'or errors may he rectified on the spot. A few strokes
of a pen will denote the extent and direction of the several
slopes much more distinctly than the brush, and if not worked
up to make a picture, will reaUy cost as little or less time. The
in-shore sides of the hills, which cannot be seen from any of
the stations, must always he mere guess-work, and should not
be shown at all. ^ .
“ I t should be considered an essential branch ot a nautical
survey, to give the perpendicular height of all remai-kable hills
and headlands. I t requires but a single angle at each station,
adds much to our geographical knowledge, matenally assists
the draftsman, and by tables whicli ai-e now printing it will
afford to the seaman a ready and exact means of knowing ins
distance. . „ ,
“ All chai’ts and plans should be accompanied by views ot the
land ; those which are to be attached to the former should he
taken at such a distance as will enable a stranger to recognize
the land, or to steer for a certain p o in t; and those best suited
for the plan of a port should show the marks for avoiding
dangers, for taking a leading course, or choosing an advanta-
o-eous berth. In all cases the angiilai- distanres and the angular
ffititudes of the principal objects should be inserted in degrees
and minutes on each of the views, by which means they can be
projected hv scale, so as to correct miy want of precision in the
eye of the draftsman. Such views camiot be too numerous;
tiiey cost but a few moments, and are extremely satisfactory to
all navigators. , • r •
“ Trifling as it may appear, the love of giving a multiplicity
of new and"unmeaning names tends to confuse our geographical
knowledge. The name stamped upon a place by the
first discoverer should be held sacred by the common consent
of all nations ; and in new discoveries it would be fai- more
beneficial to make the name convey some idea of the nature of
the place ; or if it be inhabited, to adopt the native appellation,
than to exhaust the catalogue of public characters or private
friends at home. The officers and crews, indeed, have some
claim on such distinction, which, slight as it is, helps to excite
an interest in the voyage.
“ Constant observations on the tides, including their set,
force, and duration, the distance to which they carry salt
water up the rivers, their rise at the different periods of the
lunation, and the extent to which they are influenced by the
periodic winds, by the sea currents, or by the river freshes,
form so prominent a part of every surveyor’s duty, that
no specific directions on this subject can he necessary. Nor
is there any occasion to insist here on the equally important
subject of currents; for it is only by a great a¿cunlulation
of data that we can ever hope to reduce them to regular
systems, or that w'e can detect the mode in ivhicli they are
affected by change of seasons, or influenced by distant ivinds.
The periods and limits of the monsoons and trade-wands
will naturally be a continual object of the Commander’s observation
and study. I t is true that he can only witness what
occurs during his voyage; but besides collecting facts on this
and the last subject, on which others can hereafter reason, it ivill
be of immense advantage that he should endeavour to digest
them with the remarks of former voyagers when on the spot.
On the western coast of South America, for instance, some
skill is required in making passages at different periods, and
much scattered experience has been gained by seamen who
have been long occupied there ; hut this information has not
yet been presented to the public in an intelligible form ; and
It seems to be the peculiar province of an officer expressly employed
on a scientific mission hke this, to combine that information
with Ins own, and to render it accessible to every navigator.
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