Before there was refrigeration, salt was important for its food-preservation qualities. In America's early years, Syracuse in Central New York State - aka "Salt City" - was the nation's largest producer of salt.  The postcard above shows rows of shallow evaporating pans. The sloped covers on the extreme left and right of this picture would be slid to cover the pans if it rained. See salt - very possibly from Syracuse - being used at the Fulton Fish Market in NYC in the mid-thirties at the 3:18 mark on Manhattan Waterfront. Also see the film White Wonder for an overview of the salt industry today (modern evaporating at 5:17).

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Salt City and The Erie Canal The original Erie Canal was deliberately routed to pass through what today is Syracuse, NY because of the large salt deposits that were already being harvested there by 1825 when the canal was completed. Syracuse's salt trade benefitted from the canal for two reasons: Low transportation costs, and the Erie made it more profitable for farmers all along the canal corridor to raise hogs than to grow wheat, which had been their principal crop before the canal was built. Pork required large amounts of salt for preservation. See video