150 GLACIAL GEOLOGY OF GREAT BRITAIN

run magnetic N. 43° W., i.e. true N. 64° W. (the variationbeing 21° W., add 21° W. to reading).

On top of this is a good section of a raised beach, inwhich the stones lie in bands, with a quantity of shells.The stones lie flat with the shells, thus :

Flu. 24. - Bands of Stones and Shells on Till liaised Beach (Howth ).

stcn es

with

shells

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There are many shells, broken and whole, often delicate,though lying among large stones. The parallelism of layersis constant. A side view show's this raised beach to bemade of large stones, which lie on a till made of smallerstones. Delicate shells lie among the large boulders.

We go to the north side of the island near HowthLodge, where is a good artificial exposure of limestone till,in which are no shells, overlaid by a marine deposit, con-sisting of a loamy or alluvial deposit, full of marine shells,in fragments or whole, but not rolled. There is gravellyloam on the top.

The shells are solen, fusus, littorina, patella, &c., &c.

The top of this ‘ raised beach ’ is about 30 feet abovethe sea.

Probably it is the same deposit which contains shellson the railway from Dublin to Drogheda .

Mr. McHenry says the raised beaches in Co. Antrim goup to 75 feet, and are proved by shells, by caves, and bypillars, &c., Ac.