Caption: Benjamin Franklin (1706--1790): printer, journalist, philosophe, polymath, scientist, inventor, politician, diplomat, statesman, patriot, Founding Father of the United States.

In the painting, Ben's doing experiments in electricity. The small balls are being held apart by the repulsion of the Coulomb's law force (AKA electric force) for like electric charge. Outside is lightning and a lighting rod---his own invention from 1752 (see Wikipedia: Lightning rod: United States).

By the by, Ben Franklin gave positive charge and negative charge their names. Actually, old Ben sort of blew it since conventionally electrical current flows from positive to negative. But it is negative charge (i.e., electrons) that make up electrical current in most technological applications and they flow from negative to positive. If he'd just switched the names ...

As for Declaration of Independence, to see how that document was written, view the archival footage video 1776 - But Mr. Adams Clip | 6:28 in the insert below (local link / general link: benjamin_franklin_videos.html).