How did Leonardo's Submarine design conceptually allow the vessel to sink and rise?

Answer

By flooding side hulls that functioned as ballast tanks

The submarine featured side hulls used as ballast tanks; flooding these tanks caused the vessel to sink, and forcing the water out allowed it to rise, mirroring modern submersible operation.

How did Leonardo's Submarine design conceptually allow the vessel to sink and rise?

#Videos

Thousands of Pages of Inventions, Ideas and Flying Machines | PBS

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