Year: 18th century - early 19th century
Painting appears to be painted on ivory judging by the image add say it was done circa 1790 give or take. I haven’t taken it apart to see if its signed but I might.
Thomas Wistar was born in 1767, in Pennsylvania, to Caspar Wistar and Mary Wistar .
Thomas had 6 siblings: Deborah Wistar , Samuel Wistar and 7 siblings
Thomas passed away in 1814, at age 47.
Grandson of Casper Wistar and Katharine Jansen well know brass button and glass maker. Founded Americas first successful glass factory in Alloway New Jersey aprox. 1739