Salt was one of colonial New Hampshire's most important products. Today it is viewed as primarily a seasoning, but in the first three hundred years of colonization, it was used more as a preservative, especially for fish. 

The early cod fisheries of New England were dependent upon the availability of salt in order to preserve their catch, so that it would last long enough for sale and shipment.  Salt was vital to tanners, in the preparation of furs and leather, for either local or export use. Salt also had vital medicinal purposes as an antiseptic.

The Native Peoples of New Hampshire appear to have used salt very little. They smoked rather than salted their fish. Possibly they made fish pemmican, as they were known to pulverize dried meat and mix it with hot fat and dried berries or other dried  fruit. From this they would make a thick paste which was formed into small cakes, and used as winter or emergency rations.

The first salt-producing business (aka salt-works) in the American colonies appears to have been at Cape Charles in Virginia, sometime previous to 1620. In 1633 salt appears to have been exported from Virginia to Massachusetts. Massachusetts had only a few options to obtain salt: import it from England, import it from Virginia, or set up a salt works of their own. The principal supply of salt was obtained by either catching seawater in shallow pools and allowing the sun to evaporate it, or by boiling sea water, although the finished product remained impure.  

By 1630 (probably earlier) a fishing settlement near the site of the present city of Portsmouth New Hampshire, commenced the first manufacture of salt in the northern colonies. It was located at the mouth of Piscataqua River on its southern bank. That area of New Hampshire, after all, was originally settled in order to promote the fur trade and fisheries.  Salt was an essential ingredient for both.

About 1626 salt-making was attempted in Plymouth MA, and a salt-maker from England was employed, but his first attempt failed. During the American Revolution, a major problem for the American colonists was breaking or getting around the British blockage on imports of European and Caribbean salt.

It has been written that Captain Sam Haley (1727-1811) found four bars of silver among the rocks on the Isles of Shoals.  With this money he reportedly erected a salt works, built a rope walk and set up a windmill on Smutty Nose, earlier known as Haley’s Island.

Janice

*Additional Reading*

-The History of Salt-

-Nudd's Salt Works-

Some Sources:
1. Science And Technology in Colonial America, by William E. Burns, Greenwood Press, 2005
2. "Notes on a Recently Discovered Indentures Relating to David Thomson of Piscataqua and Massachusetts Bay in New England," by Charles Deane, J. Wilson and Son, 1876
3. "A History of American Manufactures from 1608 to 1860," by John Leander Bishop, Edwin Troxell Freedly, Edward Young; E. Young & Co., 1866