1848.] ORMEROD ON THE SALT-FIELD OF CHESHIRE. 277 
The rock-salt was accidentally discovered in 1670 at Marbury, near 
Northwich. | 
The district generally known by the name of Northwich is locally 
divided into Hartford, Castle Northwich, and Winnington on the 
western side of the Weever; Leftwich, between the Weever and 
Dane, which there join; Witton and Northwich, having the Dane 
on the south, the Weever on the west, and Witton Brook on the 
north ; and Marbury and Anderton on the north side of the Weever. 
In Leftwich, on account of the great depth of quicksand or drift, 
few attempts have been made to find brine. A few years since a pipe 
was forced down more than 96 feet through the sand. In the re- 
maining townships the brine and salt are generally found in the same 
conditions and preserve the same levels ; they will therefore be treated 
of together. 
In the following particulars of Northwich, as well as occasionally 
elsewhere, I have incorporated portions of the information given to 
this Society by Dr. Holland in his paper on the ‘Cheshire Salt,’ 
vol. i. Trans. of Geol. Soc. (Old series), in which a particular de- 
scription of the Northwich salt is given. 
For much information and assistance in the local examination of 
this and the adjoming district I am indebted to the Rev. George 
Eaton, of the Pole near Northwich. My thanks are also due to 
Mr. Cheshire, one of the most extensive salt-proprietors here and at 
Winsford, for his ready help and the examination of the parts of this 
paper relating to Northwich. 
The depth to the upper bed of rock-salt at Northwich varies of 
course with the undulations of the surface of the land, and in a small 
degree on account of the irregularity of the upper surface of the bed. 
This depth varies from 96 to 159 feet. The depth to the upper 
stratum is stated by Holland as being 87 feet below the level of 
Witton or Wincham Brook, being at least 36 or 39 feet below sea- 
level at Liverpool. (Vol. i. p. 47 of First series of Geological Trans- 
actions.) The exact depth of, I believe, the nearest pit to the Weever 
as furnished to me by Mr. Thompson of Northwich is given before. 
The thickness of the upper bed is stated to vary from 84 to 90 
feet in the pits sunk to the north-west, decreasing near the east bor- 
der to 81 feet. It thins off towards the south-west, losmg 15 feet in 
thickness in the course of a mile. The upper surface of this bed is 
irregular, forming cones and irregular figures. Below lies a bed of 
indurated clay 30 feet in thickness, with veins of salt traversing it. 
This overlies the great bed of salt. 
The highest portion of the second or great salt-bed for a depth of 
from 60 to 75 feet consists of salt with a considerable portion of earth, 
and is not worked ; for 12 to 15 feet below this the salt is more pure, 
and from this part of the deposit the rock-salt is got; below the 
proportion of earth is as large as in the upper part, and this is not 
worked. These beds, it will be remembered, were compared with 
those just described in the Winsford district. 
Till within a few years the second bed had not been penetrated. 
At a pit at Marston, to the north of Northwich, belonging to Mr. 
VOL. IV.—PART I. ¥ 
