1751: Benjamin Franklin, flying a kite in a thunderstorm with a key at the end of the string, discovered the fact that lightning behaves like electricity and flows through conductive material.

Today: Control of electricity is one of the fundamental principles of our society. Blackouts, when electricity becomes unavailable, create major disruptions.

1751: Whaling was an important part of the economy of the New England colonies, with more than sixty whaling ships trolling the water off the coast.

Today: Environmental organizations fight to protect the rights of endangered whale species, but the world has much less use for whale meat or for whale oil to light lamps.

1751: English theologian and evangelist John Wesley was travelling almost 5000 miles every year to spread the word about Christianity, founding the denomination known as Methodism.

Today: Methodism is recognized as one of the mainstream Protestant religions.

1751: Approximately one-fifth of the...