In the mountainous district of Weardale, one of the most important North of England rivers is cradled, and into this isolated highland dale the Celtic name of the Durham river has penetrated. Almost all the English rivers have retained the names given to them by the Celts, and _avon_, _dur_, _esk_, _rhe_, and _don_, are Celtic roots repeated, over and over again, in names of streams, not only in England, but on the Continent. In the name Nent Water, in Cumberland, we have the simple name "water," and the Cymric _nant_, a hollow or valley formed by water--a common name in Wales. Writers mention Nant Lle as+ the vale of Lle; Nant Gwyrfai, the vale of fresh water; Nant Frangon, the beavers’ hollow or ravine; and Pennant, the head of the valley. The little village Nenthead, on the western slope of Killhope, is the head of the valley. From the root _dwr_, water, and the frequently occurring Celtic _gwent_, an open region, comes Derwent, the name of the stream on the north of Weardale, and of various other rivers in England. The local pronunciation, however, in the district of Derwent is _Darwen_, which suggests _dwr_ and _gwen_, the clear water. The River Wear is formed by the joint streams of Killhope and Burnhope Burns, which meet at Wearhead village. Its course through the dale is rapid, receiving many tributaries from the hopes. On reaching Auckland it takes a north-easterly course. "And now," says Camden, "the river, as though it proposed to make an island, compasseth almost on every side the chief city of this province standing on an hill, whence the Saxons gave it the name _Dunholm_. For as you may gather out of Bede, they call an hill _dun_, and a river island _holme_." The Wear, which enters the sea at Sunderland, was called _Vedra_ by Ptolemy, _Wirus_ by Bede, and in Bishop Pudsey’s time (1153-94) the name was written _Were_, the same as we find in Hatfield, 1380, Holinshed 1577, and Camden 1604. The latter form is the proper modern spelling up to about the last century, when _Were_ became _Wear_, the present form of the name of St. Cuthbert’s stream. Ferguson, on the authority of Pott, gives the Sanscrit _ud_, _udon_, water, from which comes the German _wasser_, English _water_, as the root of Ptolemy’s _Vedra_.[8] _Wirus_ suggests the Celtic _gwyrhe_, rapid water. Perhaps _gwy_ or _wy_, water, and _garw_ or _arw_, rough, form the roots. The former root enters into the names of several rivers, as the Wye, Edwy, Elwy, and others. In all the forms of spelling the river-name of Durham the letter "r" is conspicuous. It is the principal one in _arw_, which enters into the names of several streams--the Ayr, Are, Aire, Arre, being variations of this widely diffused root. The Welsh _rhe_, rapid, with _gwy_, may show equal claim to notice as first mentioned--namely, _gwyrhe_. Omitting the initial _g_ in the first, and the middle letter in the second, root, we have _wyre_.