440 Proceedings of the Royal Irish Academy. 
two flakes have come off quite close to each other, leaving a ridge 
such as we find in ordinary cores. There is a natural prong jutting 
from the core ; and if we look at the object as a whole we find that it 
would make an excellent pointed implement of the kind figured in 
Plate xxmt., fig. 5. In another section I found a flake-like flint, but 
without a bulb, having the edge partially dressed for scraping. 
I do not think anyone would doubt the artificial character of the 
flaking on these specimens.® 
Frmt Frakes From Interciactat Gravets.—I stated in the note 
at end of my Paper on Flint Implements from Larne and the North- 
East Coast,’ that I had found two flakes in gravel, capped by thirty 
feet of boulder clay. These were found at Ballyrudder, about half 
way between Larne and Glenarm. We find there a mass of gravel not 
unlike the Larne gravels in some respects, but having a covering of 
boulder clay about thirty feet in thickness, and containing shells of 
Arctic character. I have made several examinations of these gravels, 
and have now obtained ten flakes. Several of these have marks on 
the edge, as if made by scraping; but one small one is neatly dressed 
all round the edge. Two are outside flakes; seven are uncrusted ; 
two have the surface whitened, but there is no deep crust; and one 
has a deep incrustation like the Larne flakes, but the crust has been 
split off the greater part of the back. I have not the slightest doubt 
that this flake was incrusted before being included in the interglacial 
gravels. The flakes have all well-marked bulbs of percussion, and are 
similar to flakes of artificial character that we find in many other 
places in-Antrim. None of them were received from workmen, or 
obtained by examining masses. of loose material; but all were found 
by myself by slowly excavating the gravel of the section, and taking 
out with my own hands any flint object that appeared zm situ. I 
figure two specimens (see figs. 7 and 8, Plate xxm.). 
I have also obtained from these gravels several core-like flints, 
together with an object which, though rude, I consider to be of the 
same character as the large pear-shaped implements from the raised 
beach. 
Tue Burs or Percusston.—As the bulb of percussion is a principal 
test for determining the artificial workmanship on flints, this may be 
considered the proper place to say a word or two about it. I have 
made some experiments in breaking flint, and, as far as my experience 
goes, the bulb can only be produced by a blow. The cause of the 
® I also found a large pear-shaped implement with supposed glacial markings 
on an artificially dressed surface ; but as I did not find it imbedded in any forma- 
tion, and as authorities differ—one doubting the glacial character of the marks, 
and another the artificial character of the flaking—lI will withhold it for the 
present. 
7 See ante, p. 218. 
8 For a list of those shells, see Paper by Canon Grainger, M. R. 1. A., British 
Association Report for 1874, Trans. of Sections, p. 73. ; 
