The Upper Delaware, Edward Willis Redfield, oil on canvas, roughly 38 x 50 inches (96 x 127 cm).
Link is to zoomable image on Google Art Project; high res (33mb) image available on Wikimedia commons; original is in the collection of the James A Michenner Art Museum in Bucks county PA, which unfortunately does not put much effort into displaying works from their collection online.
Redfield, though not the founder, is often thought of as the leader of the group of painters who settled along the Delaware River north of Philadelphia in the early 20th century that is often referred to as the “New Hope School”, or the “Pennsylvania Impressionists”.
Refield was noted for his winter scenes, and this beautiful depiction of the Delaware River as it passes through a rocky area some miles north of New Hope is a striking example.