44r Prof. BucKLAND and Mr. De la Beche on the 



How far the causes of this inundation may be connected with the elevation 

 of the strata in the immediate neighbourhood or in distant regions^ is a sub- 

 ject which at present we conceive it premature to enter into, further than to 

 suggest that the relation of the one to the other may possibly be nearer than 

 has been hitherto apprehended. 



Diluvium. 



Although the excavation of valleys of denudation, and removal of broken 

 strata has been so considerable in all this district, we have no proportionate 

 accumulation of extensive and continuous beds of gravel. The power and 

 rapidity of the currents which could excavate the materials that filled such 

 enormous spaces must have been too great to allow these materials to subside 

 so near the spots from which they have been torn away, and must have drifted 

 them far forwards into the prolongation of these valleys in the bottom of the 

 English Channel, whence perhaps many of them may have been cast up again, 

 and have contributed to form the Chesil Bank. The largest deposit of dilu- 

 vium we have noticed is at Upway Street, four miles north of Weymouth; but 

 in smaller quantities and irregular patches it is disposed over the whole surface 

 of the country, on the summits and slopes of the hills as well as in the valleys. 



We have not heard of many organic remains in the diluvium of this district, 

 but the following are sufficient to show their identity with those found in 

 diluvial gravel in other parts of England. A few years ago a large rolled 

 molar tooth of an elephant was cast upon the Chesil Bank, from the diluvium 



the chalk-marl with such regularity as to present the uniform width and uniform grassy slopes of 

 the deep foss of a military fortification, and affords a similar measure of the amount of the power 

 of existing agents on a substance of such uniform and perishable materials as soft chalk-marl. 



The following list of the temperature of springs in the neighbourhood of Weymouth was taken 

 by Professor Henslow, with a good thermometer, in the year 1832 : — 



20th August. Well at Chesilton, in Portland stone, near the middle of the ascent in 



the yard of the Portland Arms. A pump was used 54° 0' 



24th August. Spring at Preston, by the road side, in the Portland sand 53° 0' 



28th September. Large spring at Upway, the source of the river Wey, rising suddenly 



in great force from a cross fracture of the Portland rock 51° 0' 



20th Septemper. Pump at Corfe Castle 52° 5' 



20th September. Hill side (vertical strata), half way between Corfe and Worbarrow 



Bay, junction of chalk and sands 52° 0' 



4th September. Top of Headon Hill, Isle of Wight : spring from the upper freshwater 



formation, a few feet from the summit 50° 0' 



5th September. Spring issuing from the sand rock under the fire-stone at Knighton. . . .51° 0' 

 Where the temperature was taken in pump-water, it was not done until all the water that had 

 filled the pipes was removed by long pumping. 



