What is this invention?
Fire
What is this invention?
Light Bulb
What is this invention?
Paper
What is this invention?
Wheel
What is this invention?
Sewing Machine
What is this invention?
Telephone
What is this invention?
Airplane
What is this invention?
Phonograph
What is this invention?
Ramp
What is this invention?
Wedge
What is this invention?
Screw
What is this invention?
Doorknob
What is this invention?
Axe
What is this invention?
Compass
What is this invention?
Satelite
What is this invention?
Electronic Battery
