56 BULLETIN OF THE NEW YORK STATE MUSEUM 



ployed * on the quality of the fuel.f the physical conditions 

 of the latter, on the state of the weather, the temperature of 

 the air, amount of heating surface, height of brine in the 

 kettle, thinness of metal through which the heat has to 

 be transmitted, on the more or less perfect combustion of 

 the fuel, on the temperature at which the brine is evapo- 

 rated, etc. 



3 STEAM EVAPORATION 



Steam Kettle Process 



There are two salt blocks in the Wyoming Valley at 

 Warsaw in which the Onondaga kettles are used for the 

 manufacture of salt, but these kettles are heated by steam 

 instead of direct fire. Hence in place of the brick arches 

 in which the kettles are hung at Syracuse, they are supported 

 by a frame work, and each kettle is surrounded by a steam 

 jacket covered with a non-conductor. Moreover the metal 

 of the kettle is made much thinner for the better transmission 

 of the heat. The steam enters the jacket at the upper end 

 of the kettle and at one side and the condensed water escapes 

 by a valve below it, to be returned to the steam boiler. The 

 method of manufacture of the salt does not differ in any 

 particular from the Onondaga method. The heat of the 

 steam being uniform for all the kettles, the salt produced is 

 uniform in grain and very good in quality. The number of 

 the kettles under one roof or in one salt block can be varied 

 according to the wish of the manufacturer and the steam 

 capacity of the boilers. 



The quality of the salt is primarily dependent on the at- 

 tention of the workman, on the chemical composition of the 

 brine, on its proper settling, on the length of time a block 

 has been in operation, and on the amount of calcium and 

 magnesium chlorides present in the pickle, since an exces- 

 sive heating of the front kettles, especially when they are 



* See table of brine strength, etc., No. i. 



t See table 2. This table was compiled from Prof. W. B. Johnson's experiments 

 made for the navy. 



