Oeological Society of London. 129 



Mr. Evans disputed Mr. Mallet's conclusions as to the propagation of motion 

 through ice and the effects of grounding icebergs. 



Mr. Tiddeman had examined much of the western coast of England opposite to 

 Ireland, and did not attribute its glaciation to any general ice-sheet radiating from 

 the Pole. The glaciation in the valleys he regarded as of later date than that of the 

 ice-sheet, and it was to be studied as a separate phenomenon. The ice-sheet he con- 

 sidered to have been general over the north of England, and its shed ran along the 

 Pennine chain. Its tendency would be rather to form a series of parallel valleys than 

 any radiating from a common centre. 



Mr. J. Clifton "Ward stated that in Cumberland he had found that the direction of 

 the ice must, near Skiddaw, have been in a northerly direction. 



The author, in reply, remarked that in Greenland, whatever might theoretically be 

 the case, ice is pushed for scores or hundreds of miles down into the sea, until it gets 

 out of its depth, and eventually floats off as icebergs. He pointed out the corre- 

 spondence of the main valleys of Ireland with glaciations on the surface of rocks from 

 Scotland, and exhibited specimens and rubbings in illustration of various characters 

 of weathering and wear from different natural causes. 



III.— February 5, 1873.— Warington W. Smyth, Esq., F.R.S., Vice-President, 

 in the Chair. — The following communication was read : — "On the Oolites of 

 Northamptonshire. Part II." By Samuel Sharp, Esq., F.S.A., F.G.S. 



In the First Part of this Memoir the succession of beds in the neighbourhood of 

 Northampton was shown to be as follows : 



Clay 



"White Limestone i p, <. n Tf 



Clay with Ferruginous Band > ^^^^^ ^°^'^^- 



("Upper Estuarine") 



Line of Unconformity. 



/ Sand with Plant Bed , 



Northampton) ("Lower Estuarine") Ire ■ r> v. 



Sand ..... Variable Beds I'^f^""^ Oolite. 



\ Ironstone Beds / 



Upper Lias Clay. 



The Great Oolite limestone of this section has been confounded, even up to the 

 present time, with a limestone (frequently Oolitic) which occurs between Kettering 

 and Stamford, is prevalent about the latter town, and extends through Rutland nnd 

 Lincolnshire (where it attains a thickness exceeding 200 feet) into Yorkshire ; which 

 limestone has been distinguished by Mr. Judd as the "Lincolnshire limestone." The 

 object of the author was to show that these two limestones were distinct, and that 

 while the former was of the Great Oolite period, the latter as certainly belonged to 

 the period of the Inferior Oolite ; and in citing evidence in proof of this position 

 upon stratigraphical and palasontological grounds, he gave a general account of the 

 geologyof the northern division of Northamptonshire, illustrating his description by 

 the exhibition of numerous fossils gathered from the various beds and localities 

 referred to. 



Between _ Northampton and Kettering, the Great Oolite limestone is the surface 

 rock ; and intersecting valleys upon that line, and the escarpment of the Ise valley, 

 a mile east of Kettering, exhibit this sequence of beds : 



Great Oolite Limestone. 



M „ Upper Estuarine Clays. 



. Inferior Oolite Lower Estuarine Beds ) Northampton 



„ _ , Ferruginous Beds ) Sand. 



Upper Lias Clay. 



And this section, with the successive superaddition of Great Oolite Clay, Cornbrash, 

 Kelloway Rock, and Oxford Clay, is continued due east across the country to the 

 valley of the Nene, and on into Huntingdonshire. 



Upon the same Ise escarpment, about a mile north-east of Ketteriug, the thin end 



VOL. X. — NO. cv. 9 



