If the principal becomes insane and unable to exercise an intelligent direction of his business, his condition operates as a revocation or suspension for the time being of his agent's authority. If on recovering, he manifests no will to terminate his agent's authority, it may be considered as a mere suspension, and his assent to acts done during the suspension may be inferred from his forbearing to express dissent when they come to his knowledge. Likewise an agent's insanity terminates or suspends the agency for the time being unless he has an interest of his own in the matter. Partial derangement or monomania will not have that effect unless the mania relates to the agency, or destroys the agent's ability to perform it.
Again, the marriage of a principal in some cases, unless a statute has changed the common law, will revoke the power previously given, especially when its execution will defeat or impair rights acquired by marriage. Thus should a man give a power of attorney to another to sell his homestead, but before effecting a sale the principal should marry, his marriage would revoke the power. By marrying the wife acquires an interest in the property which cannot be taken away from her without her consent by joining in a deed of conveyance with her husband. Likewise the marriage of a woman would operate to revoke a power of attorney previously given by her whenever its execution would defeat the rights acquired by her husband. An agent's marriage usually will not affect the continuance of his agency.
When an agency is terminated it is often needful for the principal to notify all customers for his protection, otherwise they might continue to do business with the agent, supposing he was thus acting, and involve him perhaps in heavy loss. This rule applies especially to partnerships, each member of which is an agent with general authority to do the kind of business in which it is engaged.
If the authority of an agent in writing is revoked, but is still left with him and is shown to a third person who, having no knowledge of the revocation, makes a contract with him, the principal will be held for its execution.
Another rule of law may be given. The law assumes that any knowledge acquired by an agent concerning his principal's business, will be communicated to his principal, who is bound thereby. This rule though is often difficult to apply. Thus, if a cashier of a bank should learn that a note was defective, which was afterward discounted by his bank, it would be regarded as having knowledge of the defect, because it was the cashier's duty to inform the proper officials before they discounted it.
The death of either agent or principal terminates the agency except in cases of personal interest. And when an agent has appointed a substitute or subagent without direct authority, and for his own convenience, the agent's death annuls the authority of the subagent or substitute, even though the agent was given the right of substitution. But if the subagent's authority is derived directly from the principal, it is not affected by the agent's death.
Agreement to Purchase Land.—An agreement to purchase land must be in writing to be valid. Oral or parol agreements may be made to do many things, but everywhere the law makes an exception of agreements relating to land purchases. A statute that is quite similar in the states requires this agreement to be in writing and signed by the party against whom it is to be enforced. Thus if the seller wishes to enforce such an agreement, he must produce a writing signed by the purchaser; if the latter wishes to hold the seller, he must do the same thing. The better way is to have the writing signed by both parties.
How complete must the writing be? It need not mention the sum to be paid for the land; it can be signed with a lead pencil: a stamp signature will suffice. The entire agreement need not be on one piece of paper. If it can be made out from written correspondence between the two parties this will be enough.
To this rule of law are some exceptions. Therefore if an oral agreement for the sale of land is followed by putting the buyer into possession, the law will compel the seller to give him a deed. The proceeding would consist of a petition addressed to a court of equity, which would inquire into the facts, and if they were true, would compel the seller to give the purchaser a deed of the land. The reason for making this exception is, the purchaser would be a trespasser had he no right to be there: to justify his possession the law permits him to prove, if he can, his purchase of the land; and if he has bought it, of course he ought to have a deed of his title.
Once, a purchaser who made an oral agreement and paid part of the purchase money could compel the seller to give him a deed, and many still think such action is sufficient to bind the bargain. This is no longer the law. The practice gave rise to much fraud: A would assert that he gave money to B to pay for land when in truth it was given for some other purpose. So the courts abandoned the rule founded on the part payment of the purchase price. A can however get back his money.