MACKIE — EAMBLE IN THE NORTH OF FRANCE. 
129 
the inclination differs on either side, as we see to be the ease with 
the ripples of sand which the strong current of a spring-tide makes 
on the seashore. We tliere see fragments of shells, or other compa- 
ratively large objects carried rapidly down the longer descending 
planes, and slowly up the sides ot the steeper banks, and deposited 
beneath the crests of the waves. As the drifted shells render thus 
apparent to the eye the arrangement and disposition to which the 
grains of sand composing the bed of the shore are subjected, so by 
the disposition of the flints in the clays and sandbeds it seems to me 
we might interpret the directions and actions of the powerful flow 
that spread the drift over such extensive tracks of country. At least, 
whether we admit flood-action or not in the spread of the superficial 
deposits, a series of correct observations of such indications of the 
direction and arrangements of their contained pebbles and consti- 
tuent materials would do much towards determining the direction 
of the current or force by which those materials were brought and 
deposited. The indications of drift- movement are generally, as far 
as I observed them, towards the north, but in some cases on the 
slopes of hills the course has evidently been southerly. The pre- 
sence and form of the tongue of sand at St. Addresse seem to con- 
firm the supposition that the flint-gravel overlying the "shell-sand" 
had a southerly tendency, which would be the case if it were con- 
tinuous with the drift of St. Addresse and the high ground of Cap 
La Heve. Further observations are, however, necessary to confirm 
this opinion. 
The deposit of sand containing shells must have been originally 
very considerable, as the waste by the sea on this coast being very 
great, even on the harder rock of the cliffs, its action on such soft 
materials must have been highly destructive. 
Since writing the ab6ve, I find in jNI. Passy's excellent description 
of the department of the Seine Inferieure, an account of this recent 
shell-sand, which that author considers to be a portion of the ancient 
embouchure of the Seine. 
Passing from Havre westwards, I made collections of fossils at 
Honfleur. Dives, and all along the coast up to Caen, the quarries of 
which pour their rubble down the green wooded slopes of a lovely 
gorge into the river below,— the white city with its lofty houses and 
over-topping churches and cathedral, and the low Oolitic clifls fringing 
the blue waters of the Channel in the distance, form an enchanting 
scene worthy of a longer pilgrimage than it takes to see. 
VOL. VTI. ^ 
