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oerning them, it may not be possible to regard tbe age of the 
one as older or yonnger tlian that of the other. 
Before passing on to the secondgroupof pre-historic dwellings, 
I am inclined to remark upon one possible class of evidences to 
be obtained in certain parts of our island, as to the existence 
of another variety of dwelling- spot. Many rocky cliffs in the 
Dordogne have been observed by Mr. Christy and M. Lartet 
to be pierced with holes, arranged in lines, and having* un- 
doubted marks of design in their formation. These holes are 
always met with beneath an overhanging part of the cliff, at 
places where such a beetled brow would form a roof-tree for a 
dwelling, fixed by means of inserted poles against the face of 
the rock. Ascending lines, of holes have also been noticed, 
into which it was probable that “ rounds ” of a rude ladder 
were inserted to enable the dwellers in these “ arbres ” to 
reach their homes. Not the slightest remains of any such 
dwellings have yet been found, but the undoubted artificial 
character of the holes renders their existence probable. Similar 
holes, in precisely identical natural situations, have been often 
noticed by myself on the face of the soft red sandstone cliffs 
which form escarpments to the diluvially-scooped valley of the 
Severn, and in many lateral valleys in its near neighbourhood. 
And I would here suggest that a careful examination should be 
made in those districts, more especially along the cliffs at Kinver 
and Cookley, in Staffordshire; Kidderminster and Wolverley, 
in Worcestershire; and Bridgenorth, in Shropshire. The age 
of these dwellings is considered by the French archaeologists 
to be intermediate between the cave-dwellers (whose “ homes ” 
do not come into our list of erections) and the hut- circle men. 
One second form, or rather group, of dwellings we find typed 
by the crannoges of the Irish bogs. These, though diversely 
constructed, by being raised upon an artificial foundation of 
piles surrounding and supporting* a floor of beaten clay and 
twigs, appear to be nearly allied in character to the hut- 
circles ; and if we regard this variation in design as depen- 
dent upon the natural features of the country, they may be 
referred to the work of the same pre-Celtic people. Indeed, 
Professor Harkness, from an examination of a remarkable 
example at Drumkeerey Lough, near Bailieborough, county 
Cavan, considers that the crannoge was not originally formed 
upon an artificial island, but on land, either island or promon- 
tory, but little raised above the level of the lake ; and that its 
foundation had to be changed from a natural to an artificial one 
by reason of the peat invading the shores, filling* up the creeks, 
and so lessening the area of the lake and deepening the 
water. “The gradual rise of the water compelled the cran- 
noge-dwellers to raise their floors, and so give them the 
