We have three sources of evidence that the writings of the great classical writers were not neglected as has sometimes been asserted. These sources are: 1, the numerous works of classical authors which have been copied and preserved in the Irish monastic libraries especially those of St. Gall in Switzerland and Bobbio in Italy; 2, the marginal and interlinear glosses on various MSS. earlier than the tenth century; 3, the quotations and imitations of classical writers which are revealed by study of the actual writing of early Irish mediæval writers. In the section of Chapter V dealing with Irish libraries we discussed fully the first source of evidence and pointed out the influence of these libraries in late mediæval times. In more than one instance we had occasion to refer to the glosses as exemplifying different phases of intellectual activity in the Irish monastic school. Here we would emphasise the fact that these glosses furnish another objective proof that the Irish monks studied and taught the classics as well as the writings of the Fathers. There is considerable variety in the glosses. Generally they are in the nature of explanations written usually in Irish or Latin but occasionally in Greek. They consist mainly of explanations of obscure passages. They give various historical, mythological, and archæological details. They contain definitions, translations of individual words, free translations of idiomatic expressions, illustrations of the correct use of certain words, a summary of the observations of previous commentators and an elucidation of obscure allusions. In short they contain all that varied and supplementary matter which is essential when making an intensive study of a difficult book. These notes were at once grammatical and encyclopædic.[341]