Analysis of British and foreign salt. 393 



evaporation is carried on for 24 hours, with the brine heated 

 to l60°or 170° Fahrenheit. The salt, thus formed, is in qua- 

 drangular pyramids or hoppers, which are close and hard in 

 their texture. The remainder of the process is similar to 

 that of making stoved salt, except that, after being drained, 

 it is carried immediately to the store house, and not after- 

 ward exposed to heat, an operatiou confined to the stoved 

 salt. 



The large grained fiakey salt is made with an evapora- T.arpe grained 

 tion conducted at the heat of 130 or 140 degrees. The salt flukej * alt# 

 thus formed is somewhat harder than common salt, and ap- 

 proaches more nearly to the cubic shape of the crystals* of 

 muriate of soda. 



Large grained Qr fishery salty is prepared from brine heated Large grained 

 only to 100° or 110° Fahrenheit. No perceptible agitation, °' fishery ' 

 therefore, is produced in the brine, and the slowness of the 

 process, which lasts from 7 or 8 to 10 days, allows the mu- 

 riate of soda to form in large, and nearly cubical crystals, 

 Seldom however quite perfect in their shape*. 



For ordinary domestic uses, stoved salt is perfectly suffi- Uses of the 

 "dent. Common salt is adapted to the striking and salting £ lft * rent 

 of provision, which is not intended for sea voyages or warm 

 climates. For the latter purposes, the large grained or 

 fishery salt is peculiarly fitted. 



On the eastern and western coasts of Scotland, and espe- Scotch salt 

 •cially on the shores of the Frith of Forth, large quantities fromseawater. 

 of salt are made by the evaporation of seawater. In conse- 

 quence of the cheapness of fuel, the process is carried on, 

 from first to last, by artificial heat, at a temperature, I be- 

 lieve, equal or nearly so to the boiling point, and varying, 

 therefore, according to the concentration of the brine. The 

 kind of salt, chiefly formed in Scotland, approaches, most 

 nearly to the character of stoved salt. In some pjaces a Sunday salt. 

 salt is prepared, termed Sunday salt; so called, inconse- 

 quence of the tires being slackened between Saturday an4 

 Monday, which increases considerably the size of the crys- 

 tals. 



I am indebted to Dr. Thomson of Edinburgh (who gave Dr. Thomson. 



* Cheshire Report, p. 53, &c. 



Vol. XXVI.— July, islo. O me 



