Among the inscriptions in Maes-Howe is one which, from its apparent insignificance, none of the interpreters have condescended to notice. It will be observed on one of the loose stones lying in the foreground on woodcut No. 88, it consists of only four letters, and reads either HIAI or IKIH, according as it is turned one way or another. As it is impossible to make a recognisable word, much less sense out of such a combination, it is no wonder it was thrown aside; but it is just because it is unintelligible that it may turn out to be valuable as an index to the age of the monument. Nothing is more unlikely than that a Iorsala Farer would have idly engraved these Runes on a loose stone, but nothing more likely than that a mason who hewed the stone and fitted it to close the "loculus" exactly, would have put a mark upon it to show that it belonged to the right-hand chamber in which A or B was to be buried. The inscription is on the inner edge of the stone, where it would be hid when the stone was _in situ_, and most probably was engraved on the stone before it was originally used to close the opening. This, at least, is an explanation of its meaning better than any other which has yet been suggested, and if it is the correct one, this inscription with the Dragon and the Wurm-Knot are among the original sculptures of the tomb; and, if so, it will be difficult to assign it to an earlier age than the tenth century, which, from the circumstances to be mentioned hereafter, seems on the whole the most probable date. [Illustration: 88. View of Chamber in Maes-Howe. From a drawing by Mr. Farrer.]