Strengthen
(Alteration)

Range:  0
Components:  V, S, M
Duration:  10 years per level (or see below)
Casting Time:  1 week
Area of Effect:  Stone touched
Saving Throw:  None

This enables the wizard to carve a special rune on some structure, a wall, well, or other stone design, that will keep it sturdy and strong for the duration specified. About 250 cubic feet of stone per level can be affected. Earthquakes will not damage the structure.
After tenth level, the spell becomes permanent (until dispelled). The material components for this spell are a piece of chalk, and a set of arches constructed of steel. The wizard must analyze the structure beforehand, to place the spell appropriately.

