'An early type of this device was made by floating a magnetized piece of iron on cork in a bowl of water'
a compass
ENDS IN SS: An early type of this device was made by floating a magnetized piece of iron on cork in a bowl of water
An early type of this device was made by floating a magnetized piece of iron on cork in a bowl of water
An early type of this device was made by floating a magnetized piece of iron on cork in a bowl of water
ENDS IN "SS"
a compass
ENDS IN "SS"