Editing Edge Chronicles (section)

==The Ages of Flight==
The Edge relies heavily on sky-travel due to the sheer lethality of the Deepwoods, but flight technology changes over the 600 year period. Generally, the history of sky-travel in the setting is divided into three Ages of Flight.

The First Age of Flight: Skyships are built around buoyant, living rocks. 

The Second Age of Flight: With the extinction of the flight rocks via a mysterious plague, flight can now only be accomplished via tiny craft made from lighter-than-air wood.

The Third Age of Flight: Through the harnessing of Stormphrax, a kind of solidified lightning, large flying machines far in excess of the craft of the First Age of Flight can be built again.

In the First Age of Flight, which began long before the start of the series, flying ships are built around "flight rocks"; naturally buoyant stones that grow in a region of the Edge known as "The Stone Gardens", which ascend as they heat and descend as they cool. Further bolstered by the naturally buoyant nature of certain tree-woods from the Deepwood, large ships are constructed around flight rocks by using a combination of fire and water to manipulate the rise and fall of the stones, and sails to catch the wind.

The First Age ends when a strange phenomena called "stone sickness" mysteriously arrives in the Edge, causing flight rocks to universally lose their buoyancy and crash.

The Second Age of Flight begins when people learn to construct small 1-person and 2-person flying vessels using the old sumpwood and treated with a new varnish that enhances its natural buoyancy. However, these small vessels can only be used for personal craft, and the need to reconstruct the flight-base trade network ultimately leads to the Third Age of Flight, which centers around the harnessing of stormphrax. This proves so successful that whereas it took only a century for the First Age to end and the Third Age to begin, the Third Age is still uncontested five centuries after its beginning.