Hole

A hole is one of a small number of objects (including ocean and river) with the power to change the terrain. Once one of these objects is set (unlike most objects, they won't place unless they overlap a sufficient quantity of earth) they become a permanent part of the landscape. Once set they cannot be moved or deleted, and clicking on them has no effect. They do continue to contribute to the resource budget meter, permanently reducing the objects you have to work with on the level.
A hole is a deep chasm in the ground that can be fallen into. It appears to be impossible to jump out of on its own. It's difficult, but possible, to fit a ladder into the space created by the hole to aid Maxwell in climbing out.
A hole and ladder can be used to allow Maxwell to easily bypass the tornado in Level 2.