62 



per cent, of carbonate of lime with aljout two per cent, of iron. 

 The eleveutli and last at seTent3--two feet from the Lower Green- 

 sand is very similar to number ten, containing a large proportion 

 of lime with very little pliosplioric acid. The valuable and well 

 arranged museum at Folkestone, where the objects of local 

 intesest form a separate collection, should not be neglected and 

 indeed should be visited before going to Copt Point that the eye 

 may become familiarised with the fossils indicative of the several 

 beds. Griffiths, the well-known fossil collector, has a cottage on 

 the right hand side of the road leading to the Warren, where the 

 geologist maj" not only obtain some very fine specimens, but also 

 make himself acquainted with the fossil forms that constitute the 

 p;uide marks of his investigations. The spherical nodules scattered 

 through the various beds of the gault, called turtles' eggs, may 

 .possibly have been so, but their origin has not yet been deter- 

 mined. Mackic, wliom I have previously cj^uoted, supposed them 

 to be the remains of belemnites. Mr. Seeley has remarked that 

 these nodules have the appearance of being rolled, and that their 

 spherical exterior lias not been caused by the surface conforming 

 to the figure of the organisms which they enclose. Mr. Charles- 

 worth, at the same meeting of the Geological Society, cited in 

 conformation of these views, the globular masses at the base of 

 the shark's teeth, found in the (rag, which do not in the least 

 conform, the shape of the fossil they enclose. Phillips, page 356, 

 mentions that in some places the Gault furnishes an excellent 

 brick-earth from which light coloured bricks may be made. As 

 night gives place to day, or one season to another, the conditions 

 under which life became individualised changed, and so the 

 creatures of this geological period gave place to others or adapted 

 themselves to the altered conditions that mark the next forma- 

 tion, which as it is composed of the casts, shells, and remains of 

 what once were living things, may not unaptly be called the great 

 white cemetery of the chalk. 



At Folkestone the Gault Clay under Martcllo Tower No. 2, is 

 capped with the Upper Grcensand, which is about fifteen feet thick in 

 this place. It shows again at two or three places along the beach in 

 East Wear Bay, where it has been brought down to the level of the sea 

 by the movements going on in the underlying clay beds, caused by 

 the action of the water and the pressure of the higher part of the 

 cliffs. Its proper geological position is at the base of the chalk, it 

 is however represented here but to a small extent, thinning out to 

 the westward to three or four feet at Caesar's Camp, after which 

 there is no re-appcarancc of it until we reach Aylesfoid, where it is 

 only eighteen inches thick. When iron was so largely smelted in 

 the Weald this formation supplied the firestonc that was used for 

 lining the furnaces. Large quantities of hearth stones are now 

 obtained at Godstone from underground woikiugs, which arc said 



