Encyclopaedia Britannica > Volume 7, ETM-GOA

Sea. I, G E O G Pv
Hiftory. tempted to fix the longitudes and latitudes of the fixed
ftars, by confiSering their diftances from the equator.
One of their obfervations gave rife to the difcovery of
the preceffion of the equinoxes, which was firft obferved
by Hipparchus about 150 years after; and he made
ufe of Timocharis and Ariftillus’s method, in order
to delineate the parallels of latitude, and the meri¬
dians on the furface of the earth; thus laying the
foundation of the fcience of geography as we have it
at prefent.
But though the latitudes and longitudes were thus
introduced by Hipparchus, they were not attended to
by any of the intermediate aftronomers till the days of
Ptolemy. Strabo, Vitruvius, and Pliny, have ail of
them entered into a minute geographical defcription of
the fituation of places, according to the length of the
Ihadows of the gnomon, without taking the leaft no¬
tice of the degrees and minutes of longitude and la¬
titude.
The difcovery of the longitudes and latitudes imme¬
diately laid a foundation for making maps, or delinea¬
tions of the furface of the earth in piano, on a very
different plan from what had been attempted before.
Accounts Formerly the maps were little more than rude outlines
•of the anci- and topographical fketches of different countries. The
snt maps, earlieft were thofe of Sefoftris, mentioned by Eufta-
thius ; who fays, that “ this Egyptian king, having
traverfed great part of the earth, recorded his march
in maps, and gave copies of his maps not only to the
Egyptians, but to the Scythians, to their great afto-
nifhment.”—Some have imagined, that the Jews made
a map of the Holy Land, when they gave the different
portions to the nine tribes at Shiloh : for Jofhua tells
us, that they were fent to walk through the land, and
that they defcribed it in /even parts in a book ; and Jofe-
phus tells us, that when Jofhua fent out people from
the different tribes to meafure the land, he gave them,
as companions, perfons well fkilled in geometry, who
could not be miftaken in the truth.
The firft Grecian map on record is that of Anaxi¬
mander, mentioned by Strabo, lib. i. p. 7. It has
been conjectured by fome, that this was a general map
of the then known world, and is imagined to be the
one referred to by Hipparchus under the defignation
of the ancient map. Herodotus minutely defcribes a
map made by Ariftagoras tyrant of Miletus, which
will ferve to give us fome idea of the maps of thofe
ages. He tells, us, that Ariftagoras fhowed it to Cleo-
menes king of Sparta, with a view of inducing him to
attack the king of Perfia, even in his palace at Sufa,
in order to reftore the lonians to their ancient liberty.
It was traced upon brafs or copper, and contained the
intermediate couxitrfes which were to be traverfed in
that march. Herodotus tells us, that it contained
“ the whole circumference of the earth, the whole fea
or ocean, and all the rivers but thefe words muft not
be underftood literally. From the ftate of geography
at that time, it may be fairly concluded that by the
Jea was meant no more than the Mediterranean ; and
therefore, the earth or land fignified the coafts of that
fea, and more particularly the Leffer Afia, extending
towards the middle of Perfia. The rivers were the
Halys, the Euphrates, and Tigris, which Herodotus
mentions as neceffary to be croffed in that expedition.
It contained one ftraight line, called the Royal Higb-
Vox.. VII. Part II.
A P H Y. 633
way, which took in all the Rations or places of en- Hiftory.
campment from Sardis to Sufa. Of thefe there were J
111 in the whole journey, containing 13,500 ftadia, or
1687^ Roman miles of 5000 feet each.
Thefe itinerary maps of the places of encampment
were indifpenfably neceffary in all armies. Athenseus
quotes Baeton as author of a work intitled, 'The en¬
campments of Alexander's march ; and likewife Amyn-
tas to the fame purpofe. Pliny tells us, that Diog-
netus and Baston were the furveyors of Alexander’s
marches, and then quotes the exaft number of miles
according to their menfuration; which he afterwards
confirms by the letters of Alexander himfelf. It like¬
wife appears, that Alexander was very careful in exa¬
mining the meafures of his furveyors, and took care to
employ the moft fkilful in every country for this pur¬
pofe. The fame author alfo acquaints us, that a copy
of this great monarch’s furveys was given by Xenocles
his treafurer to Patrocles the geographer, who, as
Pliny informs us, was admiral of the fleets of Seleucus
and Antiochus. His book on geography is often
quoted both by Strabo and Pliny ; and it appears, that
this author furniftied Eratofthenes with the principal
materials for conftru&ing his map of the oriental part
of the world. $
Eratofthenes was the firft who attempted to reduce Parallel of
geography to a regular fyftem, and introduced a regu- Jiat^u'|e
lar parallel of-latitude. This was traced over certain
places where the longeft day was of the fame length.
He began it from the ftraits of Gibraltar; and it
thence paffed through the Sicilian fea, and near the
fouthern extremities of Peloponnefus. From thence it
was continued through the Ifland of Rhodes and the
Bay of Iffus; and there entering Cilicia, and crofting
the rivers Euphrates and Tigris, it was extended to
the mountains of India. By means of this line, he en¬
deavoured to re&ify the errors of the ancient map,
fuppofed to be that of Anaximander. In drawing this
parallel, he was regulated by obferving where the
longeft day was fourteen hours and an half, which
Hipparchus afterwards determined to be the latitude
of 36 degrees.
The firft parallel through Rhodes was ever after¬
wards confidered with a degree of preference, like the
foundation ftone of all ancient maps; and the longi¬
tude of the then known world was often attempted to
be meafured in ftadia and miles, according to the ex¬
tent of that line, by many fucceeding geographers.
Eratofthenes foon after attempted not only to draw
other parallels of latitude, but alfo to trace a meri¬
dian at right angles to thefe, palling through Rhode*
and Alexandria, down to Syene and Meroe ; and as
the progrefs he thus made tended naturally to enlarge
his ideas, he at laft undertook a ftill more arduous talk, 6
namely, to determine the circumference of the globe, Attempt#
by an a&ual meafurement of a fegment of one of its to deter-
great circles. To find the meafure of the earth is in- niine the
deed a problem which has probably engaged the at-
tention of aftronomers and geographers ever frnce the Circumfe.
globular figure of it was known. Anaximander is faid rente,
to have been the firft among the Greeks who wrote
upon this fubjeft. Archytas of Tarentum, a Pytha¬
gorean, famous for his Ikill in mathematics and me¬
chanics, is faid alfo to have made fome attemprs in
this way; and Dr Long conje&ures, that thefe are
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