A ship sailing with an east wind from the Pillars of Hercules must reach India after traversing 70,000 stadia, which he thought was the half-circumference of the earth along the latitude of Rhodes. The greatest circumference he calculated at 180,000 stadia. These erroneous calculations were adopted by Ptolemy, and were afterwards of great significance to Columbus.
He made a journey as far as Gadir in order to see the outer Ocean for himself, to measure the tides and to examine the correctness of the generally accepted idea that the sun, on its setting in the western ocean, gave out a hissing sound like a red-hot body being dipped into water. He rightly connected the tides with the moon, finding that their monthly period corresponded with the full moon; whereas others had thought, for instance, that they were due to changes in the rivers of Gaul.
Cæsar, 55-45 B.C.
Cæsar’s Gallic War and his invasion of Britain (55-45 B.C.) contributed fresh information about these portions of Western Europe; but it cannot be seen that they gave anything new about the North. Cæsar describes Britain as a triangle. This is undoubtedly the same idea that we find in his contemporary Diodorus Siculus, and is derived from Pytheas. Cæsar merely gives different proportions between the sides from those of Diodorus. He puts Hibernia to the west of Britain, not to the north like Strabo, and makes its size about two-thirds of the latter, from which it is separated by a strait of about the same breadth as that between Gaul and Britain. Between Ireland (Hibernia) and Britain is an island, “Mona” (Anglesey), and scattered about it many other islands. In some of them there was said to be a month of unbroken night at the winter solstice; but of this Cæsar was unable to obtain certain information. This must be an echo of the tales about Thule, which he had got from older Greek or Roman authors.
Cæsar is a good example of the Romans’ views of and sense for geography. In spite of this military nation having extended their empire to the bounds of the unknown in every direction, they never produced a scientific geographer, nor did they send out anything that we should call a voyage of exploration, as the Phœnicians, Carthaginians, and Greeks had done. They were above all a practical people, with more sense for organisation than for research and science, and in addition they lacked commercial interests as compared with those other peoples. But during their long campaigns under the Empire, and by their extensive communications with the most distant regions, they brought together an abundance of geographical information hitherto unknown to the classical world. It is natural that it should have been a Greek who, in one of the most important geographical works that have come down to us from ancient times, endeavoured to collect a part of this information, together with the knowledge already acquired by the Greeks, into a systematic statement.
Strabo, Christian era
This man was the famous geographer Strabo, a native of Asia Minor (about 63 B.C.-25 A.D.). But unfortunately this critic has nothing to tell us about the North, and in his anxiety to avoid exaggeration he has, like Polybius, been at great pains to discredit Pytheas, of whose statements he will take no account; nor has he made use of the knowledge of the northernmost regions which we see, from Pliny among others, that other Greek authors possessed. He has not even made use of the geographical knowledge which was gained in his own time during the Roman campaign in Northern Germania under Augustus, if indeed he knew of it. To him the Ister (Danube), the mountainous districts of the Hercynian Forest, and the country as far as the Tyregetæ formed, roughly, the northern boundary of the known world. He thinks it is only ignorance of the more distant regions that has made people believe the fables “of the Rhipæan Mountains and the Hyperboreans, as well as all that Pytheas of Massalia has invented about the coast of the ocean, making use of his astronomical and mathematical knowledge as a cloak.” “Ierne” (Ireland) was placed by Strabo out in the ocean to the north of Britain. He took it for the most northern land, and thought that its latitude (which would have to be about 54° N.) formed the boundary of the “œcumene.”
“For,” he says [ii. 115], “living writers tell us of nothing beyond Ierne, which lies near to Britain on the north, and is inhabited by savages who live miserably on account of the cold.” He says further [iv. 201] of this island at the end of the world: “of this we have nothing certain to relate, except that its inhabitants are even more savage than the Britons, as they are both cannibals and omnivorous [or grass-eaters ?], and consider it commendable to devour their deceased parents,[77] as well as openly to have commerce not only with other women, but also with their own mothers and sisters. But this we relate perhaps without sufficient authority; although cannibalism at least is said to be a Scythian custom, and the Celts, the Iberians, and other peoples are reported to have practised it under the stress of a siege.”
Strabo evidently attributes to a cold climate a remarkable capacity for brutalising people, and he considers that the reports of the still more distant Thule must be even more uncertain.
The breadth of the “œcumene,” from north to south, he made only 30,000 stadia, and thought that Eratosthenes, deceived by the fables of Pytheas, had put the limit 8000 stadia (== 11° 26′) too far north. Of the countries beyond the Albis (Elbe), he says, nothing is known. Nevertheless he mentions the Cimbri as dwelling on a peninsula by the northern ocean; but he has no very clear idea of where this peninsula is.