Guy Pliniy the elder, a well-known explorer and historian of the ancient world, who lived in the firstcentury, describes the following the event.
Once upon a time, Phoenician merchants here carring loads of natural soda, which they had mined in Africa. To pass the night, they landed on a sandy shore and began to prepare food. Having no stones at hand they edged the fire with big pieces of soda. In the morning, while shoving the ashes, the merchants discovered something that has sparking in the sun. It has as hard as a stone, and pure and crystal like water.
It was glass.
Till the present day we don't know for certain, how the glass production appeared on the earth. Anyway, the legend, told by Pliniy, doesn't contain anything incredible. The presence of ashes, which formed from burnt fuel, the lime shells ( the last ones usually occur in sea sand) together with wind could create necessary conditions for glass found, concerning both chemical composition and the possibility of achievement of quite high temperature on fire.
The also exist another versions of glass discovery.