GEOLOGY OF FOLKESTONE — THE GAULT. 
85 
and ever and anon brick-works and tile-kilns, like signal posts, stand 
out upon its tract. All round the chalk-hills, in their extended semi- 
circle-range, and again on the shores of the Gallic lands across the 
" naiTOW straits," through Dorsetshire, through Cambridgeshire, 
ever cut off from the white chalk hills by a green sandy belt (the 
Upper Greensand), sometimes developed into thick courses of sand 
and fu'cstonc, as in Surrey and the Isle of Wight, sometimes only a 
narrow dark green bed measurable in inches, as in Eastwear Bay, 
and cut off from the beds below — the Lower Greensand and Neoco- 
mian— by a stratum still more remarkable in its characters, value, 
and origin. 
Lign. 9. — Ammonites inten-iiptus. From the " Ammonite-stratuiu" of the Gault. 
Near the base of the Gault there streams along a single narrow 
layer of broken casts of largish ammonites.* Once measuring the 
distance from the basement-bed above referred to, or, as for years I 
have rather called it, the "junction-bed," with the handle of your 
pick, or any other ready means, strike where you will along the en- 
crusted, or debris-covered face of the cliff, there surely will your pick's 
point clatter against those hard and rugged nodules. There they 
* These casts are cliiefly those of Ammonites Benetianus, with a smaller pro- 
portion of A. interruptus. 
