SPIEIT OF GOOD BOOKS. 



321 



^ " The blocks of sandstone are very numerous and large, especially in the 



{)its nearest the high road, some measuring as much as three to four feet in 

 ength, and weighing half to one ton. 



Fig. 7.— Section at St. Acheul : side of the field adjoining the Monastery. 



" In the east of the field the sand c thins out, and is replaced by the gravel 

 d, as shown in section fig. 7, where a good many remains of the elephant have 

 been found, and but few flint implements. The beds here and throughout the 

 field, although varying in thickness, have the same general composition as 

 described in figs 5 and 6. (d is a local sand seam). 



" One chief object in visiting the pits was to discover foi myself, if possible, 

 flint implements in situ, or failing in that, to be able to certify to their dis- 

 covery by the workmen. The long fresh faces of gravel afford, together with 

 the digging for gravel in daily operation, ready ami convenient sections for 

 observation. On my first visit, notwithstanding a careful personal search, I 

 found neither bones nor worked flints. I, however, obtained a number of the 

 latter from the men, some of which were dug out whilst I was there ; and in 

 the overlying sand I found numerous land and freshwater shells. 



"Entire bones are comparatively rare in these pits, but fragments, more or 

 less worn, are tolerably common. The greater number of the bones are soft, 

 light, and friable, and without any addition to their own earthy constituents ; 

 and having lost their animal matter, they mostly adhere strongly to the tongue. 

 Some, however, have received an additional portion of carbonate of lime, 

 whereby their weight is considerably increased. The enamel of the teeth is 

 generally but little changed. Some of the fossils are more or less bleached ; 

 others are coloured by the peroxide of iron present in some layers of the 

 gravel." 



[Supplement to the " Geologist," No. 42] 



