VOL. XXXVI.J PHILOSOPHICAL TRANSACTIONS. 387 



Eper, a city of the county of Saar entirely peopled with officers of the excise, 

 and miners or wood-cutters, and is situated on the summit of a little hill, with 

 an agreeable prospect. 



The l6th of July 1724, we came from Rosenaw to Soowar with Dr. Poekin, 

 physician to the city and county, to view this celebrated salt-work, which fur- 

 nishes the finest and most pure salt of the whole kingdom. We commu- 

 nicated our intention to an officer of the salt-works, and having asked his 

 leave to go : we first descended into the works down the well by a rope, seated 

 on leathern dogs (as they term it) about 40 fathom deep; after which we again 

 descended 100 fathom, by clinging perpendicularly against the wall and sides of 

 the wells; and having again continued our journey under ground in the salt- 

 work, we then found ourselves in the cuts, and saw all the allies cut in the 

 finest rock-salt ; in the midst of which there were here and there some veins 

 of a dark grey flint. The miners work to cut this rock-salt, which they draw 

 up by a rope, and put it into a reservoir, where they cleanse it with salt-water. 

 They boil it afterwards with the same water, till it becomes of the consistence 

 of crystal, and then put it into vessels, which contain about 268lb. weight each, 

 and then send it into Silesia and other countries. 



As to the vegetable or fossil-salt, it is extremely white and transparent; 

 and in such plenty in the salt works of the county of Marmar, near Tran- 

 sylvania, where there are large entire mountains of salt, that one might furnish 

 the whole world for quantity ; as also, because as soon as cut, it grows again 

 anew in a very short time. They break and cut it; and though it appear at 

 first black, yet in pounding it becomes extremely white: and so it is with that 

 used in Hungary, for they send all the salt of Soowar into foreign countries. 

 You find almost in every inn, two stones like to those used to make mustard, 

 between which they pound and break that sort of rock-salt; and one finds 

 also in their stables, large pieces of that mineral, which the cattle lick 

 at pleasure. 



But to return to the salt of Soowar, there are sometimes in the cuts, allies 

 of rock-salt, of the most delicate blue and yellow colours. We observed, 

 that of the first colour being exposed to the sun for some days, lost entirely 

 all that beautiful ultra marine, and became white as the other rock-salt; which 

 did not happen to the yellow, which preserved its colour; but when pounded 

 both together, the salt was neither blue nor yellow, but produced a salt ex- 

 tremely white. 



Melissantes, in his new Geography, p. 228, speaking of salt-works, which 

 the Spaniards have in Catalonia, says, that there is rock-salt, the colour of 

 which is so diversified, that it comes near the rainbow, in having green, red, 

 3 D 2 



