OX THE BOCKS OP THE ESSEX DBIFT. 



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26. On the Eocks of the Essex Dbift. By the Key. A. TV. Howe, 

 M.A., F.G.S. (Bead May 11, 1887.) 



The rocks of the drift in Essex are of such great variety that it is 

 very difficult to get a really representative collection ; but I have 

 selected some two hundred specimens out of a much larger number, 

 and these, I think, may fairly be called representative, at any rate 

 of the rocks in the western and north-western parts of Essex. Some 

 of these are chips from large boulders, others are rolled pebbles. I 

 have gathered them from the surface of the land within a radius of 

 about four miles from Felstead, taking them chiefly from the open 

 fields, the lanes, ditches, and bye-roads, and avoiding the main roads 

 for obvious reasons, although no imported road-metal is used in the 

 immediate neighbourhood. A considerable number have been taken 

 out of the Boulder-clay, and some few from the gravel-beds which 

 underlie it. The village of Felstead stands upon high ground over- 

 looking the valley of the Chelmer, about six miles to the north-west of 

 Braintree and just off the highroad between Braintree and Dunmow. 

 The general appearance of this part of Essex is that of a tableland 

 which has been carved out into valleys, with gently sloping rounded 

 hills. On the slopes of these hills there are at all levels, even to the very 

 tops, beds of loamy gravel, alternating with a considerable thickness 

 of stiff yellow loam in some parts, and in others with chalky Boulder- 

 clay, patches of which lie on the tops of the hills and along the upper 

 slopes, sometimes reaching down to a considerable depth, while here 

 and there the London Clay comes to the surface. The way in which 

 the superficial deposits lie was clearly shown a short time ago by a 

 section which had been made in the railway-cutting near Dunmow. 

 Unfortunately this has become covered up again ; but at the time 

 it was made a small photograph of it was taken for me by a friend, 

 The section showed that there were between six and seven feet of 

 chalky Boulder-clay, part of which only was uncovered, resting 

 upon a layer of red and yellow laminated clays, a few inches thick, 

 overlying some twelve feet of reddish loamy gravel, consisting of large 

 and small subangular flints, quartzites, quartz-rocks, sandstones, 

 and lumps of hard chalk, these last being very plainly striated. 

 Between the chalky clay and the laminated clays a large block of 

 Jurassic limestone could be seen sticking out, and, upon examination, 

 it was found to be deeply grooved with striaB upon more than one 

 face. I had previously found a similar block sticking out from 

 under the Boulder-clay, about a hundred yards away from this section 

 in the same cutting, and this also was striated in a similar manner. 

 But besides the numerous beds of gravel, the surface is everywhere 

 strewn with fragments of rocks, rounded pebbles, and flintstones ; and 

 in cutting open grips for surface- draining, or in deepening ditches 

 and ponds, large masses of flint, rounded boulders of quartzite and 

 sandstone, and great blocks of dolerite and other rocks are thrown 



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