126 COAL-FIELD OF CLACKMANNANSHIRE. 



These bones are supposed to belong to the whale 

 or grampus tribe. From the size of the bones, the 

 animal must have been at least thirty feet in length. 



In the recent alluvial cover of the River Devon, 

 oak-trees of immense size have been occasionally 

 found ; and at the line of junction betwixt the al- 

 luvial soil of the River Forth and the old alluvial, 

 a great quantity of drift-wood is found, consisting of 

 the spray of different trees, and entire hazel-nuts. 



The old alluvial cover, named Till by agricultur- 

 ists, is a strong heterogeneous mass, composed of 

 clay, sand, gravel, and large stones, smooth and 

 rounded ; but besides these stones, there are frag- 

 ments of all the strata which are found in the coal- 

 field ; and it is worthy of remark, that these frag- 

 ments of sandstone, slate-clay and coal, have sharp 

 angles, and have not, in any degree, suffered from 

 attrition, though comparatively very soft. It is al- 

 so remarkable, that in this old alluvial cover, no re- 

 remains of shells, trees, or any of the vegetable 

 tribes have been found, although the strata of the 

 coal-field below, and upon which it rests, contain in- 

 numerable organic remains of both the animal and 

 vegetable kingdom ; and the recent alluvial, as be- 

 fore mentioned, also abounds with these. This, I con- 

 ceive, to be a most remarkable fact, worthy of the 

 consideration and investigation of the geologist. 



In the former essays, which are inserted in the 

 first volume of the Transactions of this Society, I 

 described particularly the dip and rise of the coals, 



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