Amateur Scientists Scientific advances are just beginning to appear in America. Benjamin Franklin experiments with devices to explore static electricity (center), and invents a more efficient metal fire enclosure (lower left). In the still-developing iron business, massive stone furnaces (cut-away view at top right) begin to replace much smaller smelters in Pennsylvania, and are soon copied elsewhere.

	Gifted Amateur Of all America's Founding Fathers, Benjamin Franklin is perhaps the most interested in science. He famously flies a kite in a lightning storm, with a metal key attached to the string, to demonstrate that lightning is a form of static electricity (top left).  He invents bifocals (lower left), and a cast-iron fireplace insert that is widely sold as the 'Franklin Stove' (center top). His own personal favorite invention is a musical instrument that makes sound by touching rotating glass bowls (bottom center and right).
	Gunsmith The highest level of skill is required to make the long barrel of a musket (top left). There are no drills capable of boring out the center hole, so the gunsmith starts out with a flat, slightly tapered, bar of iron. This is bent lengthwise into a long U-shape, like a roof gutter (top right). The long edges are gradually forced together, and joined by repeated heating and hammering, an inch or so at a time (center bottom). The inner bore is opened up and smoothed using a graduated set of reamers (lower right).