History: A plaque commerating Jean Luzac

The plaque reads:
"In grateful remembrance of
1746 JEAN LUZAC 1807
Friend of Washington, Adams and Jefferson
Champion of truth and righteousness
and of the cause of the United States of America
in the Leyden Gazette 1772–1785

Erected by the Netherlands Society of Philadelphia PA
A.D. 1909"

Luzac died in the powder ship explosion of 1807 in Leiden.

The plaque can be found on the Rapenburg in Leiden, the Netherlands.