Visit to the Salt Works of Zipaquera. 91 



and information of those among whom its principles are to be ap- 

 phed. 



The impure salt taken from the rock is principally used to strength- 

 en the water from the salt springs which rise in its neighborhood, 

 and contain from ten to eighteen degrees of strength ; the point of 

 saturation being twenty five degrees, regulated by an instrument 

 graduarted for that purpose. I was told that after various experi- 

 ments it was found, that water at any degree of temperature would 

 not take up more than one fourth of its weight of salt. 



The water from the salt springs is received into a large basin of 

 substantial mason work coated with cement, built in the time of the 

 Spaniards ; large lumps of the rock salt are cast in to saturate it, after 

 which it is drawn off to be filtered into large earthen pots containing 

 from seven to fifteen gallons, arranged in an arch of a very peculiar 

 construction over a furnace heated by wood and bituminous coal, 

 found in large quantities in the vicinity. From one hundred and sixty 

 to one hundred and eighty earthen pots of a sugar loaf form, are ar- 

 ranged in an arch over the furnace, (which is a large, square apartment, 

 like an open shallow cellar,) in lines beginning at each side, being 

 supported below by the faggots and coal, and at the sides by unburnt 

 bricks plastered with clay, which fill up the interstices between the 

 pots, leaving here and there, apertures for the smoke to escape; after 

 the first four hours of the process these apertures are closed up. 

 When the rows of pots approach the center, a row of the largest size 

 are ranged in the middle like key-stones to an arch, and the whole 

 fabric is supported by lateral pressure, after the wood and coal which 

 at first serve as a resting point, have burnt away and consolidated 

 the clay which is dashed in between the sides of the pots. 



The saturated salt water is at first thrown into the exposed mouths 

 of the pots in small quantities, as a glaze ; they are then gradually 

 filled up with grained salt, prepared in the ordinary manner in large 

 iron pans. For twenty four hours after, salt water of the highest 

 grade of saturation is thrown in occasionally, (the mouths of the 

 range of pots being reached by calabashes fixed to long handles,) in 

 order to consolidate the texture throughout the mass in the pots. 

 Fresh wood is cast into the furnace underneath the arch for twenty 

 four hours, and the pots are left in their position for forty eight hours 

 afterwards, to receive the heat of the cinders, which are occasionally 

 raked up. This continued heat of seventy two hours renders the 

 salt of a marble-like firmness and appearance ; being glazed on the 



