Salt Springs of Moutiers. 221 



person to imitate it in this country ; indeed, so little is known of this 

 mode of evaporation by faggots, that it has been often stated by Eng- 

 lish writers, and has recently been again gravely repeated, that it 

 consisted in throwing salt water upon burning faggots, and gathering 

 the salt that remained. This would be a mode of making salt, as 

 wise and practicable, as the nursery method of catching birds by put- 

 ting salt on their tails. 



It is obvious that water so weakly impregnated with salt as to con- 

 tain only one pound and a half in every thirteen gallons, could not 

 repay the expence of evaporating by fuel, in any country. The wa- 

 ter of the north sea contains 2^ per cent, of salt, and yet it has 

 never been attempted, that I know of, to make salt from it by evap- 

 oration with coal fires, even on the coast of Northumberland or Dur- 

 ham, where refuse coal, suited to the purpose, might be purchased 

 for l5. 6t?. per ton. In order to make salt from the saline water at 

 Moutiers, it was necessary to concentrate it by natural evaporation ; 

 and to effect this speedily, it was required to spread the surface of 

 the fluid over as large a space as possible, the ratio, of evaporation 

 being, ceteris paribus^ in proportion to the extent of the surface ex- 

 posed to the action of the atmosphere. The first attempt at Mou- 

 tiers was made in 1550, by arranging pyramids of rye-straw in open 

 galleries, and letting the water trickle through it gradually and re- 

 peatedly. By this process a portion of the sulphate of lime it con- 

 tained was deposited on the straw, and the water became concentra- 

 ted to a certain degree. It was then carried to the boiler, and fur- 

 ther evaporated by fuel. In 1730 the present buildings were erect- 

 ed by order of Charles Emanuel the third. 



There are four evaporating houses, called Maisons d'Epines (lit- 

 erally, houses of thorns). Nos. 1. and 2. receive the water from 

 the reservoir, and concentrate it to about three degrees of strength, 

 viz. they evaporate one half of the water they receive. These 

 houses of evaporation are three hundred and fifty yards in length 

 each, about twenty five feet in height, and seven feet wide. They 

 are uncovered at the top. They consist of a frame of wood, com- 

 posed of upright postSi two and a half feet from each other, ranging 

 on each side, and strengthened by bars across ; the whole is support- 

 ed on stone buttresses, about three feet from the ground, under which 

 are the troughs for the salt water to Ml into. The frame is filled 

 with double rows of faggots of black thorn, ranged from one end to 

 the other, up to the top ; they are placed loosely, so as to admit the 



Vol. XX.~No. 2. 29 



