484 Proceedings of the Royal Irish .A-ademy. 
it into an adjoining bog-hole, that was being filled up by the debris 
of the one at which they were working; also a “‘ brass hatchet” was 
found some years ago by a man named Brien. The remains of a rath 
are observable near the edge of the bog on the mainland. It is only 
noteworthy from its situation being on low ground, ‘“‘a far-seeing 
hill” being the kind of site more commonly selected for similar 
structures; for the same condition of existence, which led men to 
live on heights surrounded by earthen banks and palisades, induced 
others to found dwellings surrounded by almost similar defences on 
the water. 
However, these crannog sites in small marsh lakes are very re- 
markable; for if the question be asked, why these dwellings were 
erected in such diminutive sheets of water, it is difficult to give 
a conclusive and satisfactory answer, either as regards facilities for 
the subsistence, or the greater security of their occupiers. These 
lakes were shallow, with foul bottoms, on which the peat was already 
accumulating; therefore the fish were comparatively small and few in 
number. The sites selected were usually close to the shore ; therefore 
the distance could be easily bridged over by an enemy. ‘The water 
not being deep, and its surface sheltered from the wind, it was 
probably frozen over for more or less lengthened periods every 
winter—an opportunity for facilitating pillage, eagerly to be embraced 
by an enemy. Crannogs thus situated would, however, give compara- 
tive security from a sudden surprise during the non-winter period, and 
would be, perhaps, as secure as a fort or doon even during a severe 
frost, such as the Jrish Annals chronicle as occurring in 1156, when 
Roderick O’Connor had his boats dragged over the ice from Blein 
Gaille to Rinn Dunit, in the Co. Leitrim, where the site of a crannog 
has been discovered opposite the castle of the same name. 
