Another important class of earthen ramparts are the long lines of
fortifications, which extend for miles across the country, and must have
entailed vast labour in their construction. These ramparts were
doubtless tribal boundaries, or fortifications used by one tribe against
another. There is the Roman rig, which, as Mrs. Armitage tells us in her
_Key to English Antiquities_, coasts the face of the hills all the way
from Sheffield to Mexborough, a distance of eleven miles. A Grims-dike
(or Grims-bank, as it is popularly called) runs across the southern
extremity of Oxfordshire from Henley to Mongewell, ten miles in length;
and near it, and parallel to it, there is a Medlers-bank, another
earthen rampart, exceeding it in length by nearly a third. Near
Salisbury there is also a Grims-dike, and in Cambridgeshire and
Cheshire. Danes' Dike, near Flamborough Head, Wans-dike, and Brokerley
Dike are other famous lines of fortifications.

There are twenty-two Grims-dikes in England. The name was probably
derived from Grim, the Saxon devil, or evil spirit; and was bestowed
upon these mysterious monuments of an ancient race which the Saxons
found in various parts of their conquered country. Unable to account for
the existence of these vast mounds and fortresses, they attributed them
to satanic agency.

There is much work still to be done in exploring these relics of the
prehistoric races; and if there should be any such in your own
neighbourhood, some careful digging might produce valuable results.
Perhaps something which you may find may throw light upon some disputed
or unexplained question, which has perplexed the minds of antiquaries
for some time. I do not imagine that the following legend will deter you
from your search. It is gravely stated that years ago an avaricious
person dug into a tumulus for some treasure which it was supposed to