Knowles — Prehistoric Stone Imjilcmenis. 217 



gouge. There are many specimens of this kind. ISTo. Ill, from about an inch 

 above the edge, is equally convex on both faces, but towards the edge it 

 is ground flatter, and even hollowed at the edge, thus forming a complete 

 gouge. It is 3| inches long, and was found at Portgienone. Two ^'iews 

 are also given of No. 112. 



ISTos. 118 and 120 show a flake and an axe of the kind which is light 

 in weight as compared with the size. The flake is a very well-formed 

 specimen, slightly injured at the point, and the axe is well and finely ground, 

 with an edge at both ends. It is similar to the axes of clay-slate, and I 

 consider these implements of light weight must have been formed of a thicker 

 layer of extra fineness in the formation to which the clay-slate belongs. 

 Implements of this light substance, as far as anyone can conceive, could be of 

 no use to the early inhabitants along the Bann, and therefore I should say it 

 must have been of normal weight when the people formed it into implements. 

 The theory that some ingredient forming the rock had dissohed and escaped 

 since the implements were made was first suggested to me by Canon Grreenwell, 

 and is, I believe, a plausible one. Kinahan,in his "Geology of Ireland," frequently 

 mentions beds of " Calcareous Shale " as part of the rock comprised in the 

 Carboniferous Slate. He mentions rocks having the same characteristics of 

 the Lower Limestone Shale and Old Red Sandstone as occurring in the valley 

 of the Blackwater, where the axe 22 inches long,formed of clay -slate, was found.' 

 The clay-slate of which the Bann implements are formed nmst have occurred 

 in the form of small boulders, which have supplied the people on the banks of 

 the Bann and Lough Neagh with material for axes. If among this material 

 were some Calcareous shale, we might have such a rock as would probably 

 explain these light stone implements. If they were originally made of Lime- 

 stone shale, the lime would probably dissolve out of the implements when 

 exposed to the waters of Lough Neagh and the Bann, which have a strong 

 tendency to dissolve limestone. As a proof of this, I find that flints from 

 the Bann which have had little cavities filled with chalk when they 

 were made into implements have now lost the lime, and only the empty 

 cavities are to be seen, thus detracting greatly from the symmetry of 

 these objects. Flint implements from Larne, or other parts where exposed 

 to sea-water, are not aft'ected in the same way, and such cavities as were 

 filled with chalk when made into implements still remain in their original 

 condition. 



Some of the implements from the Bann and Lough Neagh have a pointed 

 character, and are like ground or polished picks ; others are knife-Uke, with a 



1 Wilde's Catalogue, E.I. A. 



