That a system of writing had been in use in the Mycenaean civilisation on the mainland of Greece had been known ever since the then existing evidence was collected by Tsountas and Manatt in The Mycenaean Age, published in 1897. Further evidence thereafter slowly accumulated. An inscribed stirrup jar was found at Orchomenos in 1903. In subsequent years others were discovered at Tiryns, Thebes, and Eleusis; but in the fourth volume of The Palace of Minos, published in 1935, Sir Arthur Evans could only say as regards the Greek mainland ‘ the absence of clay tablets should be rather set down to the accidents of discovery or to climatic causes ’. Four years later in 1939 Professor Blegen found in the newly discovered Palace of Nestor at Pylos an archive room with several hundred inscribed clay tablets. This number he has further increased in his resumed excavations in 1952. In recording the discovery of the House of the Oil Merchant at Mycenae in 1950 I ventured to prophesy that if the excavation of that house could be completed it was quite likely that inscribed clay tablets would be found in its ruins. In the complete excavation of that house at Mycenae in the summer of 1952 the prophecy was fulfilled and thirty-eight clay tablets were found in two of its rooms. This is a discovery of the first importance; in conjunction with the tablets from Pylos it shows that we must expect to find inscribed clay tablets in any Mycenaean palace or large private house on the Greek mainland. There must have been tablets in the palace at Mycenae but that site was badly damaged by later building above it and subsequent denudation. At Tiryns too there must have been tablets, but that site like the Mycenae palace was excavated in the 1880’s when archaeologists were not so alive to the possibilities of what might be found. A clay tablet in the earth or even just out of the earth is barely recognizable as such. Consequently the excavator himself must have a good eye for such things and train his workmen to observe and preserve even the most insignificant looking objects of clay. It is probably too late now to find tablets at Tiryns, but some presumably must still lurk in the ruins of the palace at Thebes if that site can ever be fully excavated. The Acropolis of Athens with the palace of Erechtheus presumably once had tablets, but the classical buildings and the excavations of the last century there have destroyed any hope of their survival.