In the Lower Boulder-clay of Scotland. 



39i 



scarcely add that this glacier formed only a portion of the great sea 

 of ice which mantled the land during the early stages of the Glacial 

 period. The glacier then disappears, and behind a large ice-worn 

 mass of rock ( p) which rises in the centre of the valley, a little lake 

 is formed. Into this lake the Bos prim.igenius is floated by stream or 

 freshet. As the till further up the valley towards Shillford continues 

 to exhibit intercalated beds of sand, clay, and gravel, I am led to in- 

 fer that either one large lake with a very uneven bottom, or more 

 probably a series of small lakes, may once have occupied the area be- 

 tween Caldwell and the spot where the fossil remains of the great 

 ox were obtained. When the glacier again ascended the valley, it 

 spread its moraine profonde over the surface of the deposits which 

 had accumulated in the lake or lakes. The slight twisting and con- 

 fusion of the bedding observable in some places is perhaps due to the 

 pressure exercised by the moving ice. The junction of the stratified 

 beds with the overlying till is very regular, however, and forms 

 nearly a straight line, as shown in the woodcut. But anomalies such 

 as this are not of un frequent occurrence in the lower Boulder -clay. 



Fig. 2. Diagrammatic section across the Cowdon valley, near Crofthead. 

 N.W. Railway cuttings. Cowdon Bum. S.E. 



a. Lower Boulder-clay, 

 X. Position of Bos primigenius. 



b. Stratified clay, sand, and gravel. 

 p. Porphyrite. 



I give here a diagrammatic section across the valley, showing the 

 position of the drifts, as they were to be seen at the time of my visit ; 

 but as the navvies are busily digging away at the deposit, the section 

 will not long remain in the same condition, and in due time will no 

 doubt be rendered as illegible as orthodox railway-cuttings usually 

 are. 



II. — Notes on Modern Chemistry and Physics. 

 By Bernard H. Woodward. 



IF any apology be needed for the introduction of these notes in the 

 pages of the Geological Magazine, the excuse we would give 

 is that geologists are, at the present time, being reproached, and 

 perhaps deservedly, for attempting to generalize in cases which, to a 

 great extent, depend upon chemical and physical actions, without 

 having given these sciences that amount of study and consideration 

 which their vast importance merits. 



Our object is, therefore, to endeavour to attract the attention of 

 the readers of this Journal to what is going on in these departments 



