Text on the reverse side:
Image taken from a vintage electric publicity poster. Did you know that only 10 percent of energy in a standard light bulb is actually used to create light? Ninety percent of a light bulb’s energy is used up in the heat.
Text on the reverse side:
Image taken from a vintage electric publicity poster. Did you know that only 10 percent of energy in a standard light bulb is actually used to create light? Ninety percent of a light bulb’s energy is used up in the heat.
Greeting card
Also available as