p. 475.

[55. LOCH N-ECHACH.] — Loch n-Echach, whence was it named?
Ríbh, son of Mairid, and Eocho, son of Mairid, the twain went
from the south out of Irluachair on a flitting, and separated at
Belach dá Liacc, ‘the Pass of the two Flagstones’. One of the
twain, even Eocho, went westward on Bregia and set up on the
Plain of Mac ind Oc. He (the Mac ind Oc) went to them in the
shape of a land-holder, with his nag in his hand, and told them
that they should not bide on the Plain. They said to him that they
had no power to carry their load of goods (?) without pack-horses.
‘Put,’ says he, ‘the full of the plain wherein ye stand into bundles
with their straps upon this nag, and he will carry them with you to
the place where he will lie down thereunder.’ So they went
thence till they reached Liathmuine. Therein the nag lies down
beside them, and there he stales, and made of his urine a well
which came over them. So that is Loch n-Echach, to wit, Eochu
the king and his horse’s water, which there spread out.

Howbeit Ríbh himself went around westward and set up on
Magh Find: now that was the Playing-ground of Midir and of Mac
ind Oc. In the same way Midir went to them, having a haltered
horse with him, and they put their wealth upon the horse, and he
carried it off with them as far as Magh Dairbthenn, whereon the lake
now lies. There the nag lies down and passes his urine until it
became a well, which broke over them. Ríbh is the king’s name.
Ríbh is drowned.

Whence Loch Ríbh and Loch nEchach were (so) called.

Oengus drowned haughty Echo
By means of his steed’s urine, with great speed:
Midir went — force followed him —
And drowned Ríbh on Magh Dairbthenn.

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