XXX ADDITIONAL NOTES.
of the emperor M. Aurelius Antoninus, presented their credentials
at the court of the emperor Huan-ti in Lo-yang.
Pp. 287, 288. Agricola
On the details of the Roman advance into northern Britain, see
the edition of Tacitus' Agricola by J. G. C. Anderson. In 208-211
the emperor Septimius Severus undertook several laborious cam-
paigns in Scotland, during which he probably advanced beyond
the limits of Agricola's expedition. A Roman camp (as yet
unexplored) near Aberdeen perhaps marks his farthest north. But
his son Caracalla abandoned all the territory north of Hadrian's
Wall.
It was Agricola's intention to open up Ireland at the head of
an invading force. This enterprise was vetoed by the emperor
Domitian, and it was left to stray Roman or Gallic traders to make
occasional visits to Ireland, more especially to its eastern coast,
P. 289. Germany and Scandinavia
In the reign of Nero a Roman agent of the emperor's Minister
of Sports made a journey from the middle Danube to the Baltic
amber coast by way of Moravia, Silesia and Posnania (Pliny, 37.45).
He brought back a sufficient load of amber to stud the safety nets
at the Roman beast-hunts, and he initiated a new trans-continental
$
trade-route to Sweden, the importance of which is attested by
copious finds of Roman coins on the Swedish islands. But ancient
travellers seemingly did not discover that the land of the 'Suiones,'
which they approached from the Vistula, and 'Scandinavia,' which
they entered from Jutland, were one and the same.
P, 294, n. i. The Roman frontier system
For Hadrian's Wall, see J. C. Bruce, A Handbook to the Roman
Wall(o/th ed.); for the Wall of Antoninus, see Sir George Mac-
donald, The Roman Wall in Scotland (2nd ed.). For the Roman
frontiers in Germany, see H. F. Pelham, Essays^ pp. 178 ff.;
B. W. Henderson, Five Roman Emperors, chs. 6 and 7. Details
of the other Roman frontier lines will be found in V. Chapot, The
Roman World, passim.