Some of these blades, and notably the celts from Sluie, the Hill of Fortrie of Balnoon, and Ravelston, have been thought to be tinned. An interesting paper on the subject has been written by Dr. J. Alexander Smith and Dr. Stevenson Macadam.[225] Their conclusion is rather in favour of the celts having been intentionally tinned, so as to protect them from oxidation and the influence of the weather. I think, however, that the tinned appearance of the castings for celts from Rhosnesney affords a strong argument against this feature being the result of intentional tinning; for, if so, that metal would have been applied to the blades after they had been wrought and ground into shape, and not to the rough castings, from the surface of which the tin would be certainly removed in the process of finishing the blades. A bronze hammer from France in my collection has all the appearance of having been intentionally tinned, even partly within the socket; but in this case the bronze appears unusually rich in tin, which was probably added in order to increase the hardness of the metal, and some considerable alteration of structure has taken place within the body of the metal, as the surface is fissured in all directions, something like “crackle china.” In the Antiquarian Museum at Edinburgh are other flat celts, some of them with slight flanges at the edge, from Eildon, Roxburghshire; Inchnadamff, Sutherlandshire; Dunino, Fifeshire; Vogrie and Ratho, Midlothian; Kintore and Tarland, Aberdeenshire; and other places. [Illustration: Fig. 20.—Lawhead. ¼] Some celts of this form, but with slight side flanges, have been found in the South of France.[226] A celt of this class, also in the Museum at Edinburgh, is probably the largest ever found in the United Kingdom. It is 13⅝ inches in length, 9 inches in its greatest breadth, but only 1⅜ inch at the narrow end. Its thickness is about ⅝ inch in the middle of the blade, and its weight is 5 lbs. 7 ozs. It is shown on a scale of rather more than one-fourth in Fig. 20, for the use of the woodcut of which I am indebted to the Society of Antiquaries of Scotland. It was found in digging a drain on the farm of Lawhead,[227] on the south side of the Pentland Hills, near Edinburgh. Some of the Scottish celts, both flat and doubly tapering, are ornamented on the faces. One with four raised longitudinal ribs, and two with a series of short incised or punched lines upon their faces, were among those found on the farm of Colleonard,[228] Banff; another has shallow flutings on the blade; another, E22, in the Catalogue of the Antiquarian Museum at Edinburgh, is also ornamented with incised lines. One of those from Sluie,[229] Morayshire, is cited by Wilson. [Illustration: Fig. 21.—Nairn. ½]