4 
Some of these pits are of ancient date, but others have 
been formed recently. The one which I have just mentioned 
fell in during the month of June, 1836 ; and another on the 
opposite side of the river, even more recently — in the spring 
of 1860. The subsidence was noticed by the Rev. F. H. 
Dunwell, who has kindly furnished me with the following 
particulars. He was near the river-side with some of his 
pupils, watching some men who were fishing, when he heard 
a loud noise like thunder, and on looking round, he saw at a 
little distance a mass of earth and stones rising into the air, 
and falling back again. One of the men who were fishing 
went near, and found that a pit had been formed, in which 
was a quantity of water in a state of ebullition. It continued 
in the same disturbed state during the following day. Then 
the sides began to give way and to fall in rapidly, and the 
water subsequently disappeared. At present, one side of the 
shaft is perpendicular, the other side is broken in and slopes 
to the bottom. The depth of the pit on the day after it was 
formed was sixty-nine feet ; the width, twenty- two feet ; and 
the depth of water, twenty-seven feet.* It is cut through 
the uppermost strata of the magnesian limestone, here thin- 
bedded and in small slabs ; but lying undisturbed with a 
gentle dip eastwards of five or six degrees. At a very short 
distance, and on the same side of the river, there are some 
beds of gypsum, which seem to pass beneath the magnesian 
limestone, and probably correspond with those beds of lower 
red marl and gypsum" which Professor Sedgwick has traced 
" from the confines of Nottinghamshire to the south bank of 
the Wharfe, near Tadcaster." i* He says, The deposits of 
gypsum near Ripon may belong to the lower red marl and 
gypsum, or they may be subordinate to the lower part of the 
* For these measurements I am indebted to Mr. Heslington, of Ripon. 
t Geol Trans, y 2nd series, vol. iii., p. 101, 
