contract be ultra vires in the true sense, then neither estoppel or ratification will prevent the municipality from pleading ultra vires, and thereby defeating an action brought upon the contract.

61. Partial validity.-A contract is not of necessity entirely invalid because a portion of it is ultra vires. In such case, if the portions of the contract which are within the charter powers are separable from the ultra vires portion, the latter only is void. In a leading case the city had made a contract for paving its streets, to do which it was fully authorized, and promised to give its negotiable bonds in payment therefor; but for this it had no authority. The court ruled that, though specific performance might not be decreed in behalf of the contractors, yet the action for damages was maintainable. "It matters not," said the court, "that the promise was to pay in a manner not authorized by law. If payment cannot be made in bonds, because their issue is ultra vires, it would be sanctioning rank injustice to hold that payment may not be made at all; such is not the law. The contract between the parties is in force so far as it is lawful." 21

62. Implied promise.-A municipality may be liable in assumpsit upon an implied contract to pay value for what it has received, where it has made no express promise therefor, or has made an invalid promise which will not sustain an action. The doctrine of implied municipal liability applies to cases "where money or other property of a party is received under such circumstances that the general law, inde

21 Hitchcock v. Galveston, 96 U. S. 341,

pendent of express contract, imposes the obligation upon the city to do justice with respect to the same. In general, whenever a municipal corporation receives money or property, or accepts the benefit of labor or services rendered to it, it is bound in law to make recompense therefor.23

To maintain assumpsit against a municipality, however, the money must have gone into its treasury, or been appropriated by it; and, when it is property other than money, it must have been used by the municipality or been under its control. But with reference to services rendered, the case is different. Their acceptance must be evidenced by ordinance, or express corporate action to that effect. If not originally authorized, no liability can attach upon any ground of implied contract; the acceptance, upon which alone the obligation to pay could arise would be wanting.24

Municipal contracts, whether made under express, implied, or inherent power to contract, must necessarily be confined to such subjects only as are usually proper and essential for performance of the corporate functions of the municipality. A municipality, therefore, though it may contract not only with regard to its strictly public functions, but also with regard to such municipal matters as lights, water, and power for the use of itself and its inhabitants, has no authority to embrace within its contracts such subjectmatter as manufacturing, extraterritorial railway

22 Argenti v. San Francisco, 16 Cal. 255.

23 City of Louisiana v. Wood, 102 U. S. 294.

24 Argenti v. San Francisco, 16 Cal. 255.

construction and operation, or merchandising, nor may it become surety, nor issue a circulating medium, unless such powers have been specially conferred upon it.

63. Agents.-Municipal contracts are necessarily made for the corporation by its duly constituted and authorized agencies, which may be either boards or individuals. The common council is the proper general agent of the municipality to express the agreement either by ordinance or resolution upon the municipal record. The formal execution of the memorandum or indenture of contracts is usually committed to the mayor and recorder or other appropriate executive officer. Moreover, persons contracting with the municipality are bound to take notice of the limits of the agent's authority; and a contract made by a public agent within the apparent scope of his powers does not bind his principal in the absence of actual authority. But if the contract is made by the common council as general agent of the municipality, and within the scope of the corporate powers, express or implied, the authority as agent may be presumed.

Ratification is governed by the same rule as the making of contracts. The power to make such ratification belongs generally to the common council; but it may be made by the particular municipal agency which has the power to make the original contract.

64. Mode of contracting.-Wherever the mode of negotiating and executing a municipal contract is plainly and specially prescribed and limited, such mode is exclusive and must be substantially pur

sued; else the municipality will not be bound by the

contract.

The act of incorporation becomes an enabling act. It gives municipalities all the power they possess. It enables them to contract, and when it prescribes to them a mode of contracting, they must observe that mode, or the instrument no more creates a contract than if the body had never been incorporated. Modern decisions have established the law to be that contracts of municipal corporations need not be under seal unless the charter or other legislative enactment so requires; and so it has been held that a municipality may be bound to a contract by ordinance or by a resolution of the common council, or even by parol agreement made through a duly authorized agency.

The mode of letting a municipal contract is usually prescribed by the legislature, and, as we have seen, must be pursued. The statutes and charters, though varied in phraseology, generally contain requirements that the letting shall be upon previous advertisement, and sealed bids based on plans and specifications, and to the lowest responsible bidder.

The following general rules prevail as to letting of municipal contracts: (1) That publication must be made substantially as prescribed, though it has been held that in case of emergency, where delay would work irreparable injury to the municipality, a bona fide contract, free from fraud and favoritism, and at a reasonable price, was valid without preliminary advertisement. (2) That plans and specifications for the contract may be either published in the advertisement or referred to as on file in a particular office,

or may be furnished on application. (3) That bids must remain sealed until the day specified for opening them, to the end that the municipality may have the benefit of fair competition among the bidders; that all bids must be on file within the time limited by the advertisement, and must be publicly opened at the time and place, and by the officer, prescribed by the statute, or in charge of the biddings. (4) That, where the advertisement promises a contract to the lowest bidder, the authority in control of the biddings may reject all bids unless otherwise peremptorily directed by the charter, and no right of action will lie against the city for anticipated profits of the contract.

65. Illegal contracts.-Municipal contracts, like the contracts of private corporations and individuals, are also illegal and void whenever they are contrary to law, to public policy, or to good morals. It is a fundamental rule that aldermen and officers of a municipality must not make contracts with it. This is a universal rule, unyielding in its application, and founded on the purest public policy. It prohibits municipal contracts with private corporations in which members of the council may be interested. Such contracts are said to be fraudulent in law, and hence illegal and void.

A promise to pay a public service corporation or its agents a premium for doing their duty is illegal and void. A contract will not be sustained which tends to restrain or control the unbiased judgment of public officers. This applies to a promise by a city to surrender its right to lay out a street; also to a contract binding the city authorities not to exercise their