Plato-Phaedo Socrates True earth

The true earth, viewed from above, is a sight to behold. It is marked by bright colors, some different from any colors we know. The plants are also pure and beautiful, and the mountains are smooth and made entirely out of rubies, emeralds, and other precious stones, as well as stones more precious than any of which we know.

Socrates, the earth from above 

Great Alexander diving bell

Alexander the Great's diving bell. 15th-century manuscript illustration of the 4th-century BC ruler Alexander the Great (356 BC-323 BC) being lowered into the sea in a glass barrel, an early form of diving bell. Alexander, from Macedon, become emperor of most of the known world. He was a student of the Ancient Greek philosopher Aristotle who mentions diving bells, and Alexander is said to have used them in the siege of Tyre in 332 BC. Such stories were re-told in the Middle Ages in a tradition called the Alexander romances. This illustration is from a French translation known as the Shrewsbury Talbot Book of Romances, produced in Rouen prior to 1445.

Time line underwater exploration

Ancient Greek Pottery - Cyclops

Introduction
Read also
Ancient Greek Pottery



Cyclops Eleusis neck-amphora 

Cyclops Calyx Bristish Museum

Blinding of Polephymous Louvre Museum

Sirens

Sirens were dangerous creatures, who lured nearby sailors with their enchanting music and voices to shipwreck on the rocky coast of their island.

Odysseus and the Sirens, eponymous vase of the Siren Painter, c. 480–470 BC, (Greek vase, British Museum)

See also 

Sirens Wiki

Sirens pictures archaeology