From thousands of court cases in Essex, Middlesex, and Suffolk Counties, Massachusetts, dating from 1636 to 1700, Melinde Sanborn has extracted the names of all deponents and witnesses whose ages are given in the court records of those counties. Depositions provided in early court records are among the richest sources of personal information surviving from New England's first century, and Ms. Sanborn argues that "so many people in early New England...