36 
POPULAR SCIENCE REVIEW. 
phyry, trap of many varieties, basalt with the angles partly 
rounded, and chalk flints. Similar deposits form links on both 
sides of St. Geoi'ge’s Channel, which enable us to trace back 
their origin to the granite, basalt, and chalk of the north-east of 
Ireland. Professor Jukes says : Chalk flints and pieces of hard 
Antrim chalk are found in the drift in the counties of Dublin and 
Wicklow, and along the whole eastern and southern coast of 
Ireland, at least as far as Ballycotton Bay, on the coast of 
Cork,” * And Mr. Trimmer shows that Antrim chalk has been 
drifted southward to Caernarvonshire.f 
The Flakes in Section are of ten found in true Geological 
Position. 
On much of the unreclaimed land of Cornwall, at the base of 
tlie soil, there is a layer of crushed quartz rock, provincially 
termed “ spar ; ” and when the land is enclosed for cultivation 
the first operation is to trench the soil deep enough to take out 
the “ cold spar.” The crushed quartz occupies precisely the 
same place at the base of the soil as the shattered flints and 
flakes shown in the upper stratum of the above section. I have 
found this to hold good over a wide extent of country, for my 
workmen in forming drains and roads find the flakes about 
eigliteen inches below the surface of the soil. At Berling Gap, 
near Ka-stbourne, a portion of the chalk cliff was expected to fall, 
and the farmer removed the soil, some forty feet wide and half 
a mile long, from the top of the cliff further inland ; the 
newly exposed surface is coated with shattered flints and flakes, 
some being very perfect flake knives. Near Thetford the 
• “ Mnnunl of Geology,” p. 075. 
t “ Koval Agricultural Journal,” vol. vii. p. 482. 
