[) 328) 
XXX. 
CURIOUS WATER-WORN MARKINGS ON ROCKS AT 
DOOGHBHG, CO. MAYO. 
By T. HE. GORDON, M.B., ann A. F. DIXON, Sc.D. 
[Read, Junz 16; Received for Publication, June 19; Published, Jury 23, 1908. ] 
Tue curious markings here described and illustrated are to be 
seen on the red sandstone rocks close to the coast road near the little 
village of Dooghbeg, on the north of Clew Bay. The marks have 
attracted the notice of the inhabitants, who have invented a legend 
to account for their presence; but, so far as we have been able to 
find, they have not received the attention of geologists. They 
occur on a great flat surface of sandstone, which, like the other 
beds of this rock in the neighbourhood, is tilted so as to slope 
to the south, forming an angle of about 20 degrees with the 
horizontal. It is possible to refer all the markings, of which there 
are about twenty to twenty-five more or less defined examples, to 
a single type. In each mark there is a curved or arched portion, 
the convexity of which is always directed towards the north, 1.e., 
up the slope of the rock on which it occurs. In the concavity of 
the arch there is always to be found a pit-like depression of 
varying size and depth. ‘The limbs of the arch, as they pass down 
the slope of the rock, on each side of the pit, vary in their dis- 
position. In some cases they run nearly parallel to one another, or 
are but slightly incurved ; and then, if they are short, the whole 
mark has a somewhat horseshoe-shaped outline. In other cases 
the limbs of the arch gradually approach one another and become 
confluent. As a result a somewhat pear-shaped outline is present. 
Each marking may be made up of a large number of parallel, 
fairly deep, but narrow scratches, or the outline of the mark may 
cousist of a single groove a quarter to half an inch in depth and 
half an inch wide. In size the markings vary from 43 inches to 
12 inches in transverse diameter. 
