

Mr. R. Bakewell on a Mode of manufacturing Salt. 87 



I shall endeavour to give such a description of the process 

 as will enable any 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 English writers, and has recently 

 been gravely repeated, that it consists 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 putting salt on 

 their tails. It is obvious that water so weakly impregnated 

 with salt as to contain only one pound and a half in every 

 thirteen gallons, could not repay the expense of evaporation 

 by fuel in any country. The water of the North Sea contains 

 2y per cent, of salt ; and yet it has never been attempted, I be- 

 lieve, to make salt from it with coal fires, even on the coast of 

 Northumberland or Durham, where refuse coal suited to the 

 purpose might be purchased for 1j. 6d. per ton. 



The first attempt at Montiers, in 1 550, to make salt by at- 

 mospheric evaporation, was by arranging pyramids of rye 

 straw in open galleries, and letting the water trickle through 

 gradually and repeatedly. By this process a portion of the 

 sulphate of lime was deposited on the straw, and the water 

 became concentrated to a certain degree. It was then car- 

 ried to the boiler and further evaporated by fuel. In 1 739 

 the present buildings were erected by order of Charles 

 Emanuel the Third. 



There are four evaporating houses, called Maisons d'Epines 

 (literally, 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 re- 

 ceive. These houses of evaporation are 350 yards in length 

 each, about 25 feet in height, and seven feet wide. They are 

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

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

 ranging on each side, and strengthened by bars across; the 

 whole is supported on stone buttresses, about three feet from 

 the ground, under which are the troughs for the salt water to 

 fall 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 air, and supported 

 firmly in their position by transverse pieces of wood. In the 

 middle of each Maison d'Epines is a stone building, containing 

 the hydraulic machine for pumping the water to the top of 

 the building; it is moved by a water-wheel. When the wa- 

 ter is raised to the top, it is received in channels on each side, 

 which extend the whole length of the building; from these 



long 



