Read Rub-A-Dub-Dub aloud to your child while they are taking a bath. Soon they'll be able to recite the rhyme with you from memory. Explain what a butcher, a baker and a candle-stick maker do for a living. Candles, lanterns and torches were common sources of light until well into the 19th century. Thomas Alva Edison is credited with inventing the first commercial light bulb in 1879.
