... invention was bifocal eyeglasses. People using them can see something at a distance or read something close. Lightning interested Franklin. He believed it was caused by electricity in the clouds. To test his idea, he flew a kite during a lightning storm. He fastened a pointed wire to the kite, and attached to the wire a silk string with a metal key tied to its ends. Lightning ... struck the wire, traveled down the wet string, and made the key spark. Franklin's experiment showed that lightning is a form of electricity. The next two people who tried it were killed. One useful result of hi...

• Word Count: 813
• Approx Pages: 3
• Grade Level: High School