7 
There was a remarkable fact observed by Mr. Dunwell 
which deserves notice, viz., that the rock was seen to rise 
into the air at the time of the formation of the pit. This 
has been supposed to shew that these pits are due to some 
chemical process going on in the earth, by which a large 
quantity of gas is suddenly set free, and in this manner the 
hole is hloicn out. Such an explanation, however, scarcely 
agrees with the fact that all the materials of the pit fall to 
the bottom, and not any are thrown out. What Mr. Dunwell 
saw may be accounted for by supposing that the first fall of 
the rock, which produced the sound like thunder, caught and 
compressed a certain amount of air, which immediately 
afterwards, finding vent, threw upwards a quantity of 
earth and stones. 
A Paper was then read by Mr. Lawson Tait, of Wakefield, 
entitled Recent Speculations on Primaeval Man," which, as 
it was of a partly controversial character, has not been for- 
warded for publication. 
REMARKS ON THE EXTINCT FAUNA OF THE EAST RIDING OF 
YORKSHIRE. BY MR. EDWARD TINDALL, OF BRIDLINGTON. 
[read by MR. DENNY.] 
In that part of the western boundary of the German 
Ocean between Flamborough Head and Spurn Point, is 
situated a tract of low land called Holderness, which, in 
early times, exhibited the alternate appearance of morass 
and lake, as the river Hull overflowed or subsided in its 
progress to the Humber. Trees and shrubs sprung up in 
the uncultivated land, and, spreading by degrees, formed 
large forests, which, confining the exhalations of the soil 
and obstructing the course of streams, caused the rivers to 
overflow, and stagnate into lakes and marshes. A great 
