Platt, Benjamin (1757-1833), Danbury, Litchfield, and New Milford, Conn.; Lanesboro, Mass.; Columbus, Ohio; also made compasses and surveying instruments.
Pope, Joseph (1750-1826), Boston; also made scientific instruments.
Sibley & Marble (Clark Sibley and Simeon Marble) (late 18th century), New Haven, Conn.; also made mathematical instruments.
Sower, Christopher (c. 1724-1740), Germantown and Philadelphia, Pa.; also made mathematical instruments.
Voigt, Henry (1738-1814), Philadelphia; also made astronomical instruments.
White, Peregrine (1747-1834), Woodstock, Conn.; also made surveying instruments.
Witt, Christopher (practitioner) (fl. 1710-1765), Germantown, Pa.; also made mathematical instruments.
MATHEMATICAL (GENERAL)
Condy, Benjamin (fl. 1756-1792, d. 1798), Philadelphia.
Dabney, John, Jr. (fl. 1739), Boston.