have always taken care to apprize the reader o f it, and to put him
on his guard againft giving entire credit to them; although I doubt
not, but thefe lefs authentic draughts, thus cautioufly inferted, are
to the full as correft as thofe which are ufually publilhed on thefe
occafions. For as a&ual furveysof roads and harbours, and nice and
critical delineations of views of land, take up much time and attention,
and require a good degree o f Ikill both in planning and'
drawing ; thofe, who. are defective in induftry and ability, fupply
thefe wants by bold conjectures, and fictitious, defcriptions;' and,, as
they can be no othetwife confuted than b y going on the fpot, and
running the rifque of fuffering by their mifinformatiou, they have
no apprehenfions of being detected; and therefore, when they intrude
their fuppolititious productions on the Public, they make no
confidence of boafting, at the fame time, with how much Ikill and
c-are they are performed. But let not thofe who are unacquainted
with naval affairs imagine, that impofitions o f this kind are o f an
innocent nature; for, as exaCt views o f land are the fureft guide to
a.ieaman, on acoaft where he has never been before, all fictions,
in fo interefting a matter, mul” be attended with numerous dangers,
andfometimes with the deftruCtion of thofe who are thus unhappily
deceived.
Befides thefe draughts o f fuch places as Mr. Anjon, or the /hips
under his command, have touched at; in the courfe o f this expedition,
and the defcriptions and directions relating thereto ; there is inferted,
in the. enfuing workman ample account, with a chart .annexed
to it, of a particular navigation,, o f which hitherto little more
than the name has been known, except to thole immediately etpr
ployed in i t : I mean, the track defcribed by the Manila /hip, in her
paffage to Acapulco, through the northernpart o f the Pacific Ocean;
This material article is .collected from the draughts and journals
met with o n . board the Manila gal eon, founded on the experience
of more than a hundred and fifty years practice,,and cor.roborated.in
its principal eircumftances by the concurrent evidence of all-the
Sfianijh prisoners taken in . that vefl’el... And as many of their journals,
nals, Which I have examined, appear to have been not ill kept, I
'prefume, the chart of that northern Ocean, and the particulars of
their routè through it, may be very fafely relied on by future Navigators.
The advantages, which may be drawn from an exaft
knowledge o f this navigation, and the beneficial' prOjefts that may
be formed thereon, botftin war and peace, are by no means proper
to be difcuffed in this place ; but they will eafily offer themfelves
to the fkilful in maritime affairs. However, as the Manila fhips are
the only ones which have ever traverfed this vaft ocean, except a
French ftraggler or two, which have been afterwards feized on the
coaft o f Mexico-, and as, during hear two ages, in which this trade
has been carried on, the Spaniards have, with the greateft care, fe-
creted all accounts of their voyages from the reft of the world;'
thefe rea/ons alone would authorize the iilfertiom of thofe papers,-
and would recommend them to the inquifitive, as a very great improvement
in geography, and worthy of attention, from the lingu--
Parity of many circumftances therein recited. I muft add too (what,
iii my opinion, is far from being the leaft recommendation of thefe
materials), that the obfervations of the variation of the compafs in
that Ocean, which are laid down in the chart from thefe Spanijh-
Journal's, tend' greatly to compleat the general fyftem o f the magnetic
variation, of infinite import to the commercial and fea-faring
part of mankind. Thefe obfervations were, though in vain, often-
publicly called-for by our learned countryman, the late Dr. Halley,
and to his immortal reputation they confirm, as far as they extend,
the wonderful' hypothefis he had entertained on this head, and very
nearly correfpond, in their quantity, to the predictions he publilhed
above fifty years fince, long before he was acquainted with any one
obfervation made in thofe feas. The afcertaining.the variation in
tl;at part of the world is juft now too of more than ordinary confe-
. quence,. as the.Editors of a new variation-chart, lately publilhed,
have, for want c-f proper information, been milled by an erroneous
analogy, and have miftaken the very fpecies of variation in that
northern ocean ; for they make it wefterly where it iseafterly, and
have laid it down i T or 13° different from its real quantity.