taken place since the year 1760, chiefly
under the munificent and enlightened patronage of GEORGE III. or in
imitation of these, and which have largely contributed to extend, and
almost to render perfect, the geography and hydrography of the
terraqueous globe, are intended to form a separate division, in a
subsequent part of our arrangement.

The accurate knowledge which we now possess of the form and dimensions
of this globe of earth and water which we inhabit, has been entirely
owing to the superior skill of the moderns in the mathematical sciences,
as applicable to the practice of navigation, and to the observation and
calculation of the motions of the heavenly bodies, for the ascertainment
of latitudes and longitudes. It would require more space than can be
conveniently devoted on the present occasion, to give any clear view of
the geographical knowledge possessed by the ancients, together with a
history of the progress of that science, from the earliest times,
neither do the nature and objects of the present Collection of Voyages
and Travels call for any such deduction, of which an excellent epitome
will be found in the History of Geography, prefixed to Playfair's System
of Geography.

The ancients laboured under almost absolute incapacities for making
extensive voyages or discoveries by sea, proceeding from ignorance of
the form and dimensions of the earth, and other causes. They were but
indifferently versed in the practical part of astronomy, without which,
and those instruments which have been invented almost exclusively by the
moderns, for measuring the paths, distances, and relative positions of
the heavenly bodies, it is impossible to launch out with any tolerable
success or safety on the trackless ocean. They were ignorant also of
that wonderful property of the magnet or loadstone, which, pointing
invariably towards the north, enables the modern mariner to know his
precise course, at all times of the day of night, though clouds and
thick mists may hide the luminaries of heaven from his observation,
which were the only means of direction known to the ancients.

Various systems and theories appear to have prevailed among the ancients
respecting the figure and motion of the earth; some justly enough
supposing it to be a ball or sphere, suspended in infinite space, while
others conceived it to be a flat surface, floating upon and surrounded
by an interminable ocean. The just conceptions of some ancient
phil