For the present we must devote our attention to the historical documents.

These, again, may be divided into two classes--the lost books and those which still remain.

Of the former class the principal are the CUILMENN, _i.e._, the great book written on skins; the SALTAIR OF TARA; the BOOK OF THE UACHONGBHAIL (pron.

"ooa cong-wall"); the CIN DROMA SNECHTA; and the SALTAIR OF CASHEL.

Besides these, a host of works are lost, of lesser importance as far as we can now judge, which, if preserved, might have thrown a flood of light not only upon our annals, but also on the social, historical, and ethnographic condition of other countries.