SALIFEROUS MARLS. 



31 



Mr. Leonard Horner 1 . Dr. Hastings has recently published an interesting account of 

 the saliferous district around Worcester, from which we learn, that though the springs 

 at Droitwich have been in use since the time of the Romans, it is only within these few 

 years, that rock salt has been discovered in this neighbourhood, a fact which seems in- 

 explicable when we recollect that many years have elapsed since it was shown by Dr. 

 Holland 2 , that masses of rock salt were the source of all the brine springs in Cheshire, 

 the marls of which county are precisely of the same age and composition as those of 

 Worcestershire. The account of the Droitwich springs in Nash's History of Worcester, 

 might alone have afforded sufficient evidence of the existence of a subjacent body of rock 

 salt, the trial sections detailed therein having passed through "rivers of salt" and al- 

 ternating beds of clay, marl, and gypsum, to a " rock of salt." Notwithstanding these 

 trials, it was only in the year 1828 that a Cheshire brine smeller, judging from various 

 subsidences and chasms in the marl, fixed upon Stoke Prior, three miles east of Droit- 

 wich, as a spot where productive mines might be sunk. The attempt verified the cor- 

 rectness of his opinion and led to the discovery of rock salt. The relations of these beds 

 of salt are well explained in the following section of the works at Stoke Prior (taken 

 from the pamphlet of Dr. Hastings) , which affords a good insight into the general struc- 

 ture of the red marl of this district, and shows the same association of salt with sulphate 

 of lime, as in other parts of Europe. 



6. 



m l k j i h gf ed ft. 



a. Red and green marl Ill 



b. Red and green marl with few distinct appearances of bedding, traversed by veins of 



gypsum usually vertical 1 95 



c. Redmarl, containing "rock salt, "nearly pure, distributed like thegypsum in the overlying mass. 24 



d. First layer of rock salt, red coloured and impure . . 



e. Red marl with veins of salt 3 



2nd rock salt, containing 25 per cent, of reddish marl 10 



Green marl layer 1 



Red marl with veins of salt 12 



i. 3rd rock salt 6 



j. Red marl layer with veins of salt 2 



k. 4th, or thick bed of rock salt, including from 7 to 20 feet of marl 39 



I. Red marl with veins of salt of flesh colour 24 



m. 5th rock salt ; 30 feet thick and no bottom 30 



9- 

 h. 



in. 



0 



0 

 0 

 6 

 6 

 0 

 6 

 6 

 6 

 6 

 0 

 0 

 0 



feet 460 0 



1 Geol. Trans., Old Series, vol. ii. p. 94. 2 Geol. Trans., Old Series, vol. i. p. 38. 



D 2 



