5. When the authority is particular, it must, in general, be strictly pursued, or it will be void, unless the variance be merely circumstantial. Coke, Litt. 49 b, 181 b, 303 b; 6 Term, 591; 2 H. Blackst. 623. As if it be to do an act upon condition, and the agent does it absolutely, it is void ; and vice versa. If a person do less than the authority committed to him, the act is void ; but if he does that which he is authorized, and more, it is good for that which is warranted, and void for the rest. Both of these rules, how ever, may have many exceptions and limita tions. Paley, Ag. 178, 179. An authority given by the act of the principal to two or more persons cannot be executed by one, though one die or refuse, Paley, Ag. 177 ; Coke, Litt. 112 b, 181 b; it being in such case construed strictly, and understood to be joint and not several. Story, Ag. 42 ; 3 Pick. Mass. 232; 2 id. 345; 6 id. 198; 12 Mass. 185 ; 6 Johns. N. Y. 39 ; 23 Wend. N. Y. 324; 10 Vt. 532 ; 12 N. H. 226; 9 Watts & S. Penn. 56. And an authority given to three jointly and seve rally is not, in general, well executed by two; but it must be done by one, or by all. Coke, Litt. 181 b; Bacon, Abr. Authority, C; 1 Bos. & P. 229, 234; 3 Term. 592. These rules apply to an authority of a private nature, saving in commercial transactions, which form an exception. Where, however, the authority is of a public nature, it may be ex ecuted by a majority. 24 Pick. Mass. 13; 9 Watts, Penn. 466; 9 Serg. & R. Penn. 99.
6. As to the form to be observed in the execution of an authority, where an agent is authorized to make a contract for his princi pal in it must, in general, be person ally signed by him. Story, Ag. 146; 3 Merch. R. 237 ; 1 Younge & J. Exch. 387 ; 9 Mer. Ch. 235, 251, 252. It is a rule that an act done under a power of attorney must be done in the name of the person who gives the power, and not merely in the attorney's name, though the latter be described as attorney in the instrument. Story, Ag. 147; 11 Mass. 27, 29 ; 12 id. 173, 175 ; 16 Pick. Mass. 347, 350; 22 id. 158, 161; 8 Mete. Mass. 442; 7 Wend. N. Y. 68; 10 id. 87, 271; 9 N.H. 263,
269, 270. But it matters not in what words this is done, if it sufficiently appear to be in the name of the principal. "For A B" (the principal), " C D" (the attorney), has been held to be sufficient. Story, Ag. 153; 6 B. Monr. Ky. 612; 3 Blackf. Ind. 55; 7 Cush. Mass. 215. The strict rule of law in this respect applies, however, only to sealed in struments; and the rule is further modified, even in such cases, where the seal is not essen tial to the validity of the instrument. Story, Ag. N 148, 154; Paley, Ag. Dunlop ed. 183, note; 8 Pick. Mass. 56; 17 Pet. 161. An authority must be executed within the period to which it is limited. 4 Campb. 279 ; Russell, Fact. & Bra. 315.
'7. Destruction of. In general, an authority is revocable from its nature, unless it is given for a valuable consideration, is part of a security, or coupled with an interest. Story, Ag. 476, 477 ; 2 Livermore, Ag. 308, 309; Paley, Ag. 184, 185 ; 2 Kent, Comm. 643; 2 Mas. C. C. 244, 342. It may generally be revoked at any moment before the actual exercise of it. 3 Chitty, Comm. Law, 223; Paley, Ag. 185 ; Story, Ag. fl 463, 465. The revocation may be express, as by the direct countermand of the principal, or it may be implied. See AGENCY.
S. The authority may be renounced by the agent before any part of it is executed, or when it is in part executed. Story, Ag.
478; Story, Bailm. 202. If by the express terms of the commission the authority of the agent be limited to a certain period, it will manifestly cease so soon as that period has expired. The authority of the agent is ipso facto determined by the completion of the purpose for which it was given.
See, generally, 3 Viner, Abr. 416; Bacon, Abr.; 1 Salk. 95; Comyns, Dig. this title and the titles there referred to; 1 .Rolle, Abr. 330; 2 id. 9; Bouvier, Inst. Index ; and the articles ATTORNEY, AGENCY, AGENT, PRINCI PAL.
In Governmental Law. The right and power which an officer has, in the exercise of a public function, to compel obedience to his lawful commands. A judge, for exam ple, has authority to enforce obedience to his lawful orders.