16 MR. THOMAS WARD ON THE 



of salt manufactured do not vary at all in their constituent 

 parts, but merely in the size of the crystal or " grain " as it 

 is called. To sum up the whole process in a few words, we 

 may say generally that the larger the crystal the less the 

 heat and the longer the time required to make the salt ; 

 the smaller the crystal, the greater the heat, and the less 

 time required to make the salt. Brine boils at 226 Fah- 

 renheit. Boiled salts are taken out of the pan two or three 

 times in twenty four hours ; common salt, such as is used 

 for soaperies, chemical works, &c, every two days. Fishery 

 salt remains in the pan, according to the grain, from six to 

 fourteen days ; bay salt three weeks to a month. The 

 manufacturer, by manipulating his brine, can make the 

 crystal more or less flaky or more or less solid as he 

 wishes ; but the general principle is not altered . Foreign 

 ingredients, such as gelatinous matter or alum, have very 

 peculiar effects on the brine and on the salt crystal. Bay 

 salt is made at a temperature of about 90 , fishery from 

 90 to 140 according to grain, common salt 170 to 180 . 

 There is no exactitude maintained on this point ; nor is it 

 material, as a slight variation in the grain makes no dif- 

 ference in the sale and use of the salt. 



The manufacture of salt is extremely simple, almost 

 rude ; yet the simple plan in use for ages has been found 

 to answer best in the long run. The price of salt is so 

 low, and the manufacture such a bulky one, that costly 

 and elaborate apparatus has never been found to answer. 

 Comparing the life of an ordinary open salt pan, such as is 

 used in the trade almost universally, with that of any of the 

 numberless patented pans that have been tried, it has been 

 found that it costs less to manufacture salt by it, and that 

 the pan is far easier to repair. 



The pans used in the manufacture of salt are made of 

 wrought iron, and riveted together like boilers. Under 



