490 



THE GEOLOGIST. 



NOTES AND QUERIES. 



The Deposition op Wahp. — Deah Sie, — During a short visit in York- 

 shire, I have had my attention agaui directed to the process of warping, and 

 upon which I am anxious to submit two questions. 



1st. Where does this warp come from ? 



That it comes from the sea is certain, because it is only carried on to the low 

 lands at high tides. The amount of sediment brought up these rivers, especially 

 in dry seasons, is very considerable. Upon one farm near Howden, I am told 

 that a deposit of warp two feet thick has been formed by four spring-tides, 

 which, with the intervals of neap-tides — when the land would not be flooded, 

 would occupy about two months. 



In wet seasons, when it might be expected that a larger amount of solid 

 matter would be carried into the rivers from the higher lands, the quantity of 

 warp deposited is far below the average, and that the greatest deposits are in 

 dry seasons. 



Tliis warp in the Humber and its tributaries seems to be exhaustless. It 

 has been deposited on the lands suiTOunding these rivers for a number of years, 

 and it is as abundant now as ever." 



The question tlien naturally arises, whence comes this warp ? Is it the dis- 

 integrated materials from the rocks which form the abrupt coast of Yorkshire ? 

 Throughout the whole extent of this coast the sea is constantly wearing aAvay 

 its cM's, corroding its promontories into fantastic forms, and hollowing its rocks 

 into "deep and solemn caverns." At Withemsea, Hornsea, Bridlington, and 

 niany other places, there have been remarkable encroachments of the sea with- 

 in a few years, to the destruction of some miles of surface-land. If this warp 

 be the worn materials of these rocks, why do not other rivers, such as the Tees 

 and the Tyne, deposit it on their surrounding lands ? 



This warp is procured on the low-lands adjoinmg the Humber, &c., as a sub- 



produces is a sufficient proof of its fertilizing properties. The orduiary crops 

 of wheat, for instance, average as much as six quarters to the acre, and the 

 potatos in the London market grown on these warped lands are said to be 

 preferred to any other. 



2nd. How is it that the Humber and its tributaries — the Trent, Ouse, Don, 

 &c., are the only rivers in Great Britain that deposit " warp" ? 



That there is no other river in this country wliich deposits solid matter such 

 as " warp," on the low lands that may be flooded by it at high tides I am 

 creditably informed is a fully ascertained fact. I have had but one opportunity 

 for inquiry of a friend residing near the Mersey, who teUs me, if the waters of 

 that river were allowed to overflow the adjacent lands at high tides, which is 

 sometimes done for the sake of irrigation, that no sediment Avhatever would be 

 deposited ; any deposit like the warp of the Yorkshire rivers would buiy the 

 grass to the depth of several inches, which the water was intended to invigorate. 



There is another fact or two which appears to me to have a geological bear- 

 ing, and which I will state as briefly as possible. 



Yovi wiU no doubt remember a period when the herring-fishery off Boston, at 

 what is _ called Boston Deep, was the most important and extensive herring- 

 fishery in these islands. Great Yarmouth was also justly celebrated for its 

 mackerel, and I believe it was the custom at one time to send to the reigning 

 sovereign of England the first fish of this species that was caught in those seas. 



stitute for manure ; and the prolifii 



hoih. of cereal and roots which it 



