These diplomatic documents differ from the two preceding classes inasmuch as, though executed under a departmental or personal seal, they were not merely subsidiary to the Great Seal itself. On the other hand they cannot be regarded as purely private Deeds. In some respects these instruments approach most nearly to the nature of the semi-official instruments cited below (Nos. 141—154), especially in the case of the Coket (No. 134), which was issued officially for use at the Ports. This is perhaps the best-known type of an interesting group of departmental seals, many early specimens of which have been fortunately preserved. The departmental certificate, always known as the Debenture, has, through its connexion with the Wardrobe, to some extent the force of a Departmental Warrant, though it is not connected with the issue of the Great Seal. The form resembles that of a Privy Seal Bill, or the departmental memoranda on the Fine Rolls. In its connexion with the later “spending departments,” the modern Debenture is associated with the class of Accounts or Vouchers (cf. No. 143). The execution of this instrument resembles that of the Departmental Warrant. By far the most extensive series of these official Certificates is connected with proceedings under the Edwardian Statutes of Merchants (11 Edw. I, 13 Edw. I (3)) and of the Staple (27 Edw. III (2) c. 9). These Certificates or Reports (Nos. 135—137) were made to the Chancery and were filed there.