APEIL- 



-SEPT. 1858.] Brine-Springs of Cheshire. 



115 



departure from the usual variations took place, which, ending in 

 a rapid sinking of the brine during the months of November and 

 December, originated the fears which were entertained of a gene- 

 ral failure being at hand. I have been enabled to obtain a state- 

 ment of the fluctuations in the level of the brine in a pit at An- 

 derton during the two normal years 1854-55, and the abnormal 

 year 1856, by which the matter is clearly exemplified. The shaft 

 upon which the observations were made, was between 70 and 80 

 yards deep, and the numbers given express the height in yards to 

 which the brine rose. 



1854 



1855 



1856 



January . . 

 February. . 



March 



April 



May 



June 



July 



August. . . . 

 September. 

 October. . . 

 November. 

 December. 



15-16 



10-7-35-20 

 \ Gradu- 

 \ ally re- 

 ) ceding. 



6 



7 



7 



8-20 

 20-25 

 30 



24—30 

 23—24 

 18—24 



18— 19 

 17—19 



17- 19J 



19— 19* 



19— 20 



20— 22 



18— 11 

 10—11 



By this account it is seen that in ordinary years the average 

 depth of the brine in the shaft is thirty yards in the depth of win- 

 ter, whilst in the midst of summer five yards may be taken as the 

 mean ; and the origin of the alarm in 1856 was evidently the ob- 

 servation of a diminution setting in at a period at which an increase 

 had usually happened hitherto. The fact, however, appears to 

 have been disregarded, that in the warmer period of the year the 

 supply of brine had been far more abundant than w r as generally 

 the case, nor am I aware that any attempt was made to explain 

 this part of the phenomenon. The sudden decrease was attributed 

 by those on the spot best able to form an opinion to one of those 

 dislocations of strata which frequently on a smaller scale cause the 

 occasional failures in the supply of brine : a sudden subsidence of 

 land in one part of the Northwich district, to the depth of a three- 



