a86 Geological Ohfervatiom en the Vk'tnlty of Hull and Sever y. 



been evidently performed under water; for at a certain height the gravel ceafes to be found, 

 and the line is diftindtly marked by the particles at that level being rounded, the confequence 

 of agitation, as on the fea-beach. 



The depth of the chalk rock is not known ; it has been bored into 50 feet below the 

 Humber; the height at Riplingham, or top of the wolds, is about 400 feet. 



The low land, which ftretches from the bafe of the hills to the fea, whofe clifF forms the 

 firing of the bow, may again be divided into warp-land and alluvial : the former is uniformly 

 level, and would be covered every high tide by the Humber, were it not reftrained within 

 proper limits by embankments. The latter, or alluvial, is uneven ground, and rifes by a 

 gentle afcent to the fea cliiF. This ground is partly gravel, partly clay, varioufly mixed with 

 fliells, and with, here and there, particles of culm or powdered coal. The clifF, in fome parts, 

 js near 100 feet above the level of the fea. 



The depth of the warp is nearly the difference of the tide, being about 22 feet; below 

 this warp is found a ftratum of vegetable mould, or moor earth, in which have grown trees of 

 s great fize : this ftratum is about three feet deep, and may be found continued on the other 

 fide of the Humber, and may be feen at low ebb of fpring-tides on both fides at the fame 

 level. Below this morafs is found a bed of fand mixed with fmall particles of carbonated 

 wood, chalk, clay, and fait water, fufficient to form what is called a * quick-fand, varying in 

 depth according to the diftance from the hills. Below the bed of fand is found a ftratum of 

 clay more or lefs thick and compact, and beneath this the chalk rock (a continuation of the 

 loweft ftratum of the hills), which declines towards the Humber and the fea about five yards 

 >nthe mile ; generally under this clay, and on the furface of the chalk rock, lies a refervoir of 

 water kept down by the clay : when this clay is perforated, the water rifes to its level, and, if 

 well piped, will flow over the warp. This water breaks out at the bafe of the hills, at a 

 place called Spring-Head, and is conveyed to Hull for the fupply of the inhabitants. 



The moor earth has been univerfally found at the fame level wherever the ground has 

 been bored, and may be found along the courfe of the Humber within low-water mark, and 

 along the fea co^ft from the Spurn to Bridlington. Although I have no pofitive fa£ts that 

 the morafs extends under the alluvial part of Holdernefs, yet I have fome reafon to conclude 

 it does from the following circumftance : the morafe at Seathorn or Withernfea, along the 

 coaft, which is only vifible at the loweft ebb, is not one hundred yards from the cliffy 

 Sixty yards of the cliff have gone into the fea within the memory of many now alive, and 

 there are writings, &c. of many cliff clofes being transferred or afligned, whofe identity is be- 

 yc«id the memory of any one at prefent living, and therefore I conclude the cliff extended 

 over this morafs. It may be fuggefted that this bog is the bottom of a mere or mar, fimilar 

 to that at Hornfea, where trees have been found : but there is no mention of any fuch mar 



• When Mr. Dodd, in the year 1797, fuggefted to me the poffibility of making fubtcrraneous paffages 

 under rivers, I fhcwed him the imprafticability of it here, from the annexed fefiion, owing to the nature 

 of this quick-fand, which defeats every attempt at well-making, by blowing up in the night the labour of 

 the day. 



near 



