Other remains of log-walled huts have been found in Irish lake-dwellings, particularly in Ulster. The most interesting example yet known--one indeed that is unique among those hitherto discovered in the lake-dwellings of Europe--is that described by Captain Mudge in 1853. It lay 16 feet beneath the surface of a bog at Drumkellin, near Inver, County Donegal; and, not allowing for the lake depth, at least 26 feet of bog must have grown on the site since its erection. Within the hut was found a stone hatchet, the cutting edge of which is said to have exactly fitted certain indentations which were observable in several of its timbers, all of which were of oak. Dr. Keller found that the piles used in the construction of the dwelling at Ober Meilen had been cut with stone implements; and experiments made on green timber with the stone axes found on the site clearly demonstrated the fact.[109] The Drumkellin hut was perfectly square in plan, 12 feet each side, and 9 feet high. ‘The framework was composed of upright posts and horizontal sleepers mortised at the angles, the end of each upright post being inserted into the lower sleeper of the frame, and fastened by a large block of wood or fore-lock.[110] The interstices were filled with a composition of what appeared to be grease and fine sea-sand. The interior was divided by a flooring into an upper and a lower chamber, which were probably only used as sleeping-apartments. Portions were found of the gates of the staked enclosure within which it stood, resting on a floor of hazel branches covered with fine sand. There is a model of this hut in the Royal Irish Academy collection. At Kilnamaddo, County Fermanagh, and other places, remains of log-huts have been found. The huts at Kilnamaddo were of a very primitive kind, and lay buried under 17 feet of peat; they were but 4 feet in height and constructed of oak beams. Some of these showed long clean cuts; and others, 7 feet in circumference, had mortise-holes pierced through, which could only have been done with metallic instruments. The remains at Dunshaughlin--or, more correctly, Lagore--crannog, though probably of later date than the Drumkellin hut, were very similar to it in character; they, however, presented no upper chamber.[111]