92. Limitations contingent on the exercise of a power.

There may be an alternative independent gift to a class, valid if a power has not been exercised in a certain way, but capable of being invalidated by the exercise of the power. The explanation of such cases is referable to the distinctive legal qualities of a power and of the estate created by a power1. For example, where there is a gift to children with power to appoint life estates to a husband or wife, and an ultimate gift to grandchildren living at the determination of the prior interests, including any appointed to the husband or wife, the