The material of Tírechán appears almost entirely in Parts II. and III. But there are considerations which suggest that it was not derived merely from Tírechán, but from the older written material from which Tírechán himself selected the memoranda which he has recorded. The compiler certainly used Tírechán’s memoir, which was accessible to him if he wrote at Armagh; but he has added supplements which produce the impression of having belonged to the original records and not of being later interpolations. (Cp., for example, the account of the altar in Sliab Húa-n-Ailella, p. 94, and of the inscriptions at Selce, p. 106.) It would, perhaps, be impossible to prove this directly, but there is another fact connected with the sources of the Life which enables us to establish the probability indirectly. The Life contains a great number of notices of acts of Patrick in various parts of Ireland which are not recorded by Tírechán, but which are closely similar in character and style to the acts which he records. Now we know that this material existed in the eighth century. For in the _Additional Notices_ in the _Liber Armachanus_ (ff. 18 vᵒ b, 19 rᵒ), as we have already seen (above, p. 254), we find the greater part of it indicated by a series of memorial words (names of men and places), most of which (not all) are explained in the _Tripartite Life_, Parts II. and III. The _Tripartite Life_, therefore, contains a considerable body of ancient material, homogeneous with the material which Tírechán worked into his memoir, and not to be found elsewhere. We have a means for controlling it in the collection of jottings in the _Liber Armachanus_, and an attempt to discriminate later accretions might be successful within certain limits. For an analysis of the _Tripartite Life_ in connexion with the jottings, see Dr. Gwynn’s _Introduction_, chap, vi., with _Appendix_. 8. _Vita Tertia_