VOL. XVI. (1) THE OLD-RED-SANDSTONE 81 
SOME REMARKS 
ON 
THE OLD-RED-SANDSTONE CONGLOMERATE 
OF 
Vie POREST ‘OF DEAN 
AND 
THE AURIFEROUS DEPOSITS OF AFRICA 
BY 
Cc. G. CULLIS, D.Sc., F.G.S. and L. RICHARDSON, F.G.S. 
Near the top of the Old Red Sandstone, almost wher- 
ever it occurs in the British Isles, are conglomerates 
largely made up of quartz-pebbles embedded in a red 
sandy matrix composed of quartz-grains of various sizes. 
The Forest of Dean area is no exception. The con- 
glomerate beds rise up from beneath the Carboniferous 
rocks on all sides, and crop out high up in the steep 
hill-sides that overlook on the west and north the usually 
less elevated tracts of Herefordshire and Monmouthshire, 
and on the east the Lower Severn Valley. 
The conglomerate beds are sedimentary deposits, and 
their constituents have been derived from older rocks ; 
but under precisely what geographical conditions in the 
_ Forest area—as in many other areas besides—is not yet 
certain. The fact that they are sedimentary in origin, 
however, shows that their present basin-like arrangement 
G 
