586 MR. O. A. SHEUBSOLE ON THE 



Elm-Lodge estate* which has been largely worked for road- 

 material ; and the sections exposed from time to time have presented 

 some features of interest. The gravel here rests npon an uneven 

 surface of the buff-sand of the lower part of theWoolwich-and-E-eading 

 series. It consists of subangular ochreous flints, whiter near the 

 surface, in a more or less sandy matrix, particularly in the lower 

 portion of the deposit, with pebbles and boulders of brown and purple 

 quartzites, white quartz, sandstone, &c., and occasionally fragments 

 of igneous and metamorphic rocks. 



In certain parts of this gravel, however, there are included 

 masses of a gravel distinct in character, except that quartzites are 

 found in both. This is a clean whitish gravel containing many 

 small water-worn flints weathered white by change in the iron- 

 oxide, larger fragments of black flint, irregular lumps and pebbles of 

 chalk, and fine chalk material. Incrustations of calcite appear on 

 some of the flints. Chalk also occurs in the hollows of others. 

 It is evidently, as regards the greater portion of it, the result 

 of the wasting of a Chalk district. These included masses of gravel 

 vary in size and shape : some are lenticular or flat ; others are 

 roughly circular in section, and the materials composing them lie 

 at such an angle as seems to require the support of the ochreous 

 gravel by which they are surrounded. They have the appearance 

 usually of being contemporaneous with the other gravel, as the lines 

 of bedding seem frequently to pass through both. Black stains, due 

 to manganese, also affect both gravels equally. 



As the gravel has been worked away eastward the masses of the 

 chalky gravel exposed have been larger in number and size. The 

 sketch (fig. at page 585) will give some idea of the manner in which 

 they occur. Some of these are 10 or 12 feet in diameter in 

 their shorter axis, and extend some distance horizontally. Many 

 rest on the floor of Eeading Sand ; others, as seen in the section, 

 are entirely inclosed by ochreous gravel. The workmen think that 

 they all ultimately touch the bottom. 



Whether the two different gravels were here laid down contem- 

 poraneously or not is difficult to decide. Possibly stranded and 

 piled-up ice inclosed portions of the frozen bottom of another part 

 of the old river, and melted among the accumulating deposit. But 

 more probably the chalky gravel may have been an earlier deposit, 

 partly worn aM^ay, and covered unequally by the ochreous gravel. 

 At all events the chalky gravel was accumulated rapidly, for some 

 of the fragments of Chalk are angular, and chalky mud still fills 

 cavities in the flints. 



The patches are most numerous near the base of the gravel and 



* Sometimes called the " Grovelands Pit." See Dr. Stevens' notes in the 

 Transact. Brit. Archaeol. Assoc, March 1881 ; Proceed. Geol. Assoc, vol. viii, 

 1884-5, p. 347 ; and Ibid. vol. ix. 1886-7, p. 211 ; and Jouru. Anthrop. Instit. 

 for 1884, pp. 192-200. 



Grovelands is the next farm westwards, where there are other gravel 

 sections of less interest, although I have found a few worked flints there. The 

 prominent gravel ridge commences with the Elm-Lodge Estate, occupies its 

 southern boundary, and extends also further east. 



