N.H. Rev. Stat. Ann. § 22:6

The county of Merrimack is bounded thus: Beginning at the northeast corner of Franklin; thence southerly and easterly by the easterly line of Franklin and the southerly line of the county of Belknap to the county of Rockingham; thence southwesterly by the county of Rockingham to the north line of Manchester; thence westerly and northerly by the lines of Manchester, Goffstown, Weare, Deering and Hillsborough to the east line of Washington; thence northerly by the easterly lines of Washington, Goshen, Sunapee and Springfield to the westerly line of Danbury; thence northerly by the westerly line of Danbury to Alexandria; thence southerly by the easterly line of Danbury to Hill; thence easterly and southerly by the northerly and easterly lines of Hill to the bound first mentioned.