Philadelphia — William Davenport (1778-1829); surveying and mathematical 



Continued instruments. 



William Dean (P-1797); surveying and nautical instruments. 



George Evans (fl. 1796, d. 1798); mathematical instruments. 



Martin Fisher (fl. 1790); glass instruments. 



Joseph Gatty (fl. 1794); barometers, thermometers, and 

 philosophical instruments. 



Bryan Gilmur (end of 18th century); mathematical instruments 

 and clocks. 



Thomas Godfrey (1704-1749); improved reflecting backstaflF. 



John Gould (fl. 1794); nautical, surveying, and optical instru- 

 ments. 



Theophilus Grew (fl. 1753), practitioner. 



James Ham (fl. 1754-1764); mathematical instruments. 



James Ham, Jr. (fl. 1780); mathematical instruments. 



Alloysius Ketterer (fl. 1789); glass instruments. 



Anthony Lamb (1703-1784); mathematical instruments. 



Thomas Pryor (fl. 1778); mathematical instruments. 



Benjamin Rittenhouse (1740-C.1820); surveying and astro- 

 nomical instruments. 



David Rittenhouse (1732-1796), practitioner; astronomical 

 and surveying instruments. 



Christopher Sower [Sauer] (c. 1724-1740); mathematical instru- 

 ments and clocks. 



Charles Taws (fl. 1795); mathematical instruments. 



Henry Voight (1738-1814); clocks, watches, and astronomical 

 instruments. 



John Whitney (fl. 1801); mathematical and optical instruments. 



Thomas Whitney (fl. 1798-1823); mathematical and optical 

 instruments. 



John Wood (fl. 1790); compasses. 

 Pittsburgh: Frederick A. Heisely (1759-1839); clocks and mathematical 



instruments. 

 West Bradford: Joel Baily (1732-1797), practitioner. 



RHODE ISLAND 



Newport: William G. Hagger (c. 1744-1 830?); quadrants. 



King & Hagger (1759/60); mathematical and nautical instru- 

 ments. 

 Benjamin King (1707-1786); mathematical and nautical 



instruments. 

 Samuel King (1748-1819); mathematical instrument. 

 Paul Pease (fl. 1750); quadrants. 

 Providence: W^illiam Hamlin (1772-1869); mathematical, astronomical, and 



nautical instruments. 



164 



