This venerable instrument, the least impaired Gaelic Harp existing, is known as Queen Mary's Harp, and belongs to C. Durrant Steuart, Esq., of Dalguise, near Dunkeld. Of Gaelic Harps we can only reckon seven that may be dated earlier than the eighteenth century, the oldest being the Queen Mary and Lamont Harps, now in Edinburgh, and the harp named after Brian Boru (Boromha), preserved at Trinity College, Dublin; these three dating anterior, perhaps long anterior, to the fifteenth century. The Queen Mary and Brian Boru Harps are the two most nearly resembling one another. They are small, the Queen Mary Harp being only 31 inches high and 18 inches from back to front. They were played resting upon the left knee and against the left shoulder of the performer, whose left hand touched the upper strings. The comb is from 2-1/2 to 3-1/4 inches high. It is inserted obliquely in the sound chest, and projects about 14 inches. The sound chest, in shape a truncated triangle hollowed out of the solid, is 5 inches wide at the top and 12 at the bottom, the depth being 4-1/2 inches. The bow or forearm measures in a straight line 27-1/2 inches, the chord of the arc of the inner curve being 23 inches. The front of it is expanded so as to form a convenient hold for the hand; it tapers slightly above and below, and ends both ways in boldly carved heads of animals of a symbolical character. The strings were of brass and twenty-nine in number, and were made to sound by the player's finger-nails, which were allowed to grow long for the purpose. The Queen Mary Harp has had another (the lowest) string attached later. This string measured 24 inches, the highest treble string 2-1/2 inches; what compass the harp had it is now impossible to decide, but, following the tradition of Irish harpers, the accordance was based upon the old diatonic scale with the minor seventh, sometimes replaced by the major seventh. We learn by the lectures of the late Dr. Eugene O'Curry that the ancient Irish had three modes in their music, the "Crying," the "Laughing," and the "Sleeping." Whatever these tunings were, and probably the Highland Scotch had the same, their secret is locked up in the wood of the harps that once responded to them. In this, and frequent instances in these Plates, the instruments are not represented as strung. It is impossible to keep old instruments with that strain continually upon them, and to string them only to have them drawn would have been attended with many disadvantages.