Mariner's compass · its navigational purpose

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HistoryOne small aha

Your new ahaFinding direction.

A magnetic compass aligns with the local magnetic field. Source: Compass ↗

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36Printing press · what it reproduced in multiple copiesRECALL
Texts and images in many copies.
Movable-type printing transformed the speed and scale of book production in Europe.
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37This Mainz craftsman is associated with Europe's influential movable-metal-type printing press.RECALL
Johannes Gutenberg.
His workshop in Mainz produced printed books in the fifteenth century.
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38Mechanical clock · what it made easier to coordinate across a communityRECALL
Shared time.
Public clocks helped organize work, worship, markets, and urban life around visible hours.
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