NATURAL HISTORY SOCIETY OF GLASGOW. 153 



the volume of the river, if filled from bank to bank, must have 

 been considerable; the average width, about 200 feet, being as 

 wide as the Clyde at Glasgow Green. On the surface there is no 

 appearance whatever to indicate that such a channel exists, as it 

 is all uniformly covered by the boulder clay, which is cut into to 

 the depth of about 20 feet by the railway to Landridge, almost 

 immediately over where the channel is intersected by the drifts 

 alluded to. In the section of the bore at A on plan, this clay 

 occupies the first 60 feet, and in that at C the first 37 feet. 



From all these circumstances conclusions may be drawn as to 

 the age and history of this river. The composition of the 

 lowest layer as cut through in the drift, and the depth to 

 which the water had worn awaj'' the rocks, point to a long 

 continuation of a rapid current, which ultimately flowed through 

 a gorge with sloping sides, about 80 or 100 feet below the level 

 of the surrounding country. Taking the bore at A for our 

 data, the correctness of which I before explained is fully borne 

 out by what is seen in the coal workings which strip the channel 

 to the rise; this rapid current is indicated by 3 feet of sand and 

 gravel 110 feet from the surface. At this period the land appears 

 to have begun to sink, and a turbid stream with slower current 

 has been the result; from this the finely stratified, somewhat siliceous, 

 mud has been deposited to a thickness of 17 feet, which shows a 

 still gradual sinking. This is succeeded by 33 feet of sand and 

 gravel, during the deposition of which the water has been com- 

 paratively clear, although not necessarily of quicker current, and 

 from its great thickness the subsidence still seems to have 

 continued. When this had been finished, the point at which tlie 

 changes which ushered in the boulder clay had arrived. During 

 its deposition the whole surrounding country assumed a somewhat 

 uniform undulating surface, and the gorge, in which the river 

 had flowed, was filled up, having received 23 feet greater depth 

 of clay at A than at C. 



The bottom of the channel, where cut through, is about 300 feet 

 above the present bed of the Clyde, at the point where it would 

 intersect it if continued in the same course as it seems to be 

 keeping; and the distance is about 3 J miles. To gain that 

 level it must have flowed at an inclination of about 1 in 50, which 

 would give a current of great rapidity, or it may have gone over 

 one or more falls. A stream of such magnitude flowing so near 



