2. Assignments, § 3*—when assignment of wages by attorney in foot under power of attorney invalid. An employee cannot by an attorney in fact authorized by a power of attorney entered into before a contract of employment was made assign his wages to be earned under such contract of employment.3. Pbincipai, and agent, § 122*—when acts of special agent valid. Where a principal authorizes a special agent to perform an act in the name of the principal upon certain conditions, it devolves upon the agent to show those conditions were in existence at the time of the performance of the act, or afterwards waived.4. Assignments, § 3*—when assignment of wages invalid. Where a special agent is only authorized to execute an assignment of wages under a power of attorney at a time when the principal was indebted to the assignee and no indebtedness existed at the time of the assignment, such assignment is invalid.