78 H. M. Brydone — Further Notes on the Trimmingham Chalk. 



under this clay in the cliff and also under clay to the northward, 

 its other boundaries being formed by sand. It appeared to represent 

 the top (or rather a section across the upper part) of a flat ridge 

 running and sinking in the usual direction about 30° south of east. 

 Its southern and eastern ends were capped by a practically continuous 

 sheet of flint, identical in appearance with a sheet of flint which. 

 I had previously observed on the foreshore close by coating one 

 side of a ridge of 0. lunata chalk heading in this very direction. 

 The brickfield chalk recorded in my previous pamphlet I have 

 never seen again, but once or twice in 1900-1904 there just showed 

 through the sand some way further down the beach a nari"Ow ridge 

 of 0. lunata chalk once visible for as much as 30 yards, and 

 apparently running out to sea in much the usual direction, and in 

 a line with the first recorded brickfield chalk. This ridge has been 

 frequently just visible during 1905, and in October, 1905, it was 

 gradually exposed to a length of over 66 yards. It was nowhere 

 more than 4 feet and rarely more than 2 feet thick, and dipped very 

 steeply to the north. It seemed very remarkable that such a long 

 thin ridge should have been preserved on a foreshore, though there 

 were strong indications that it increased greatly in width at a v§ry 

 short distance deeper down. But a still more remarkable thing 

 was revealed on close examination, i.e. that throughout practically 

 its whole length it was composed of a layer of 0. lunata below and 

 a layer of grey to white chalk above, separated by a grit bed full of 

 rolled flints and chalk, and agreeing most exactly, except for its 

 greater thickness (maximum at least 6 inches) and the greater size 

 of the flint pebbles, with the grit bed at the base of the grey chalk 

 in the north bluff over a mile away. I have little hesitation in 

 identifying the two grit beds, for though the brickfield chalk above 

 the grit bed was not uniformly grey, it contained many hardened 

 and apparently rolled lumps of chalk. I could not find there any 

 of the characteristic grey chalk fossils, but the total amount of chalk 

 exposed was very small, and the physical identity is very pronounced. 



EXPLANATION OF PLATES. 



Views of Tiimmingham Chalk Bluffs, Norfolk Coast. 

 Various \'iews of the North Bluff and the exposures in the bays oh either side of it. 



Plate IV. 



Fig. 7. — Photograph taken November, 1904. 

 ,, 8.— South "bay ; November, 1904. 

 ,, 9. — Head of north bay from top of bluff ; May, 1905. 



Plate V. 



Fig. 10.— North bay, showing slab of chalk on end in cliff ; April, 1905. 

 ,, 11. — Showing slab of chalk and mass of stratified shingle on end ; Mav, 1905. 

 ,, 12.— North Bluff, seaward aspect; May, 1905. 



{To be concluded in our next number.) 



