In spite of the admitted neglect of this auxiliary historical study, to which reference has been made above, the fact that materials exist for such a provisional classification as that which has been attempted below is decidedly encouraging.

At the same time it would be found that the distribution of this special literature is somewhat uneven. The “Bibliography of Bibliographies” is almost entirely supplied by foreign scholars, and the same remark must apply to the “General Authorities” in the shape of modern treatises on this subject. For the purpose of the following table, publications dealing with the diplomatic documents of the sister kingdoms are included only in the interests of a comparative method of study, though for the most part the forms of Irish and Welsh instruments differ little from our own.

The distinction that can be made between the works of an earlier and a later period of diplomatic study is noticeable and important. It will also be remembered that we owe our only Formula Books to the former period; but on the other hand we are far better equipped than our ancestors in respect of Facsimiles and adequate texts. Indeed we can afford to pay little attention to the class of Transcripts which supplied them with most of their examples and which are answerable for many misconceptions and positive errors.

On the whole, however, the strength of our native diplomatic literature will be found to lie in the special studies of a few mediaeval scholars which have been published during the last twenty years in certain journals.