where a beneficial consideration and a request are, necessarily, implied from the moral obligation under which defendant was placed.' 5 C. J. 1397.

"Since it is alleged that the supervisors 'refused to participate in the erection or construction of said bridge or to contribute or agree to contribute any part of the cost of erecting or constructing the said bridge' it would seem that the plaintiff will be unable to so amend its complaint as to state a cause of action, but a court cannot assume that the facts may not be different from those alleged and therefore the plaintiff will be given ten days within which to amend its complaint if so advised."

As before stated, plaintiff declined to amend its complaint and judgment followed for defendant. Plaintiff's counsel argue with apparent confidence that a cause of action was stated in the first count whatever may be said of the second cause of action, and hence it was error to sustain the demurrer on both counts. Their position as stated in their reply brief is, that "regardless of any statute on the subject the County of Shasta is liable to the City of Redding, upon quasi-contract for one-half of the cost of the construction of the bridge," relying upon the cases of Hunt v. City of San Francisco, 11 Cal. 250, and Brown v. Board of Education, 103 Cal. 531, [37 Pac. 503]. Special reliance is placed upon City of Clinton v. Hickman County, 160 Ky. 687, [170 S. W. 11], a case decided by the Kentucky court of appeals. More fully stated, the contention of plaintiff is as follows: "Having been furnished by the city with a full opportunity to join in the erection of this boundary bridge in order to discharge the joint duty of the county and the city to keep this public highway open across the Sacramento River for the use of the public, and the allegation that such bridge was a public necessity and necessary for the convenience of the public being admitted on this demurrer, the county is estopped from claiming that the bridge was not built by the joint action of the county and the city. Thus, on this demurrer, the facts. are that the bridge was a public necessity in order to keep open a public highway across a boundary stream and that the county refused to participate in its erection. By refusing to participate in the erection of the bridge, the county waived any right to insist upon the bridge being jointly constructed, and cannot now evade its just liability by claiming

that the bridge was not jointly constructed. Under these circumstances, a beneficial consideration and a request are necessarily implied from the moral obligation under which the county was placed when the bridge was completed and thrown open to the public by the city."

When, and under what circumstances, an implied liability of one municipality to another municipality will arise, opens a field of discussion which we do not think it necessary to explore. The facts in the case, we assume, are as fully shown in the second cause of action as they can be. Unless plaintiff can recover under the facts there shown and admitted by the demurrer, plaintiff cannot recover at all. Hence, we deem it unnecessary to further consider the sufficiency of the first count. Plaintiff's case must stand or fall upon the facts alleged in its second cause of action.

We find ourselves in accord with the views expressed by the learned trial judge upon the second cause of action and will take the liberty of quoting them:

"This is an action brought by the City of Redding to recover from Shasta County the sum of $28,235.53 alleged to be due as the county's proportionate share of the cost of a bridge across the Sacramento River.

"The river forms the boundary line between the city and Road District No. 4.

"Some three years ago the city trustees duly determined that the public interest and necessity of the city demanded the construction of a free bridge across the river. The trustees thereupon conferred with the supervisors of the county with the object of securing the co-operation of the latter in the construction of a bridge by the city and county jointly. The supervisors refused to participate in the construction of the bridge or to contribute towards the cost thereof. The trustees then proceeded to construct the bridge at the expense of the city and have brought this action to recover from the county one-half of such expense.

"The plaintiff claims the right to enforce contribution under the provisions of section 2714 of the Political Code, which reads as follows: 'If the road overseer of one district, after five days' notice from the overseer of an adjoining district to aid in the repair of a bridge in which each are interested. fails so to aid, the one giving notice may make the necessary repairs, and must be allowed a pro rata compensation there

for by the board of supervisors out of the road fund of the defaulting district. Bridges crossing the line or lines between cities or towns and road districts, or between cities or towns, may be constructed and maintained by the cities or towns and from the road fund of the road district or by the cities or towns into which such bridges extend. Any such bridge may be constructed by contract let as provided by law by either city or town or by the county into which such bridge extends or wherein such bridge is located, and any such city, town or county may contribute toward the cost and expense of the construction or maintenance of such bridge by the appropriation for such purpose of any funds in the treasury of such city, town or county not otherwise appropriated, upon such terms and conditions as may be prescribed by ordinance or resolution of the governing body of such city, town or county aiding in the construction or maintenance of such bridge; provided, that if the proportion to be paid by any such city, town or county cannot be otherwise determined, the cost of construction or maintenance of any such bridge shall be borne equally by the city or town and from the road fund of the road district or by the cities or towns into which such bridge extends. The proceeds of any bonds heretofore or hereafter authorized by the voters of any such city, town or county for the acquisition, construction or completion of any such bridge, or any portion thereof, may be expended or contributed as herein provided.'

"Counsel for the plaintiff contend that the terms of the statute must be construed as mandatory, invoking the familiar rule that where a public body or officer has been empowered to do an act which concerns the public interest it becomes the duty of the public body or officer to do it. There is no doubt as to the correctness of the rule but there is just as little doubt that the rule is not of universal application. Permissive language authorizing official action is often held to be mandatory but on the other hand mandatory language is sometimes held to be permissive only. No hard and fast rule is to be applied in such cases but the court must look to the nature of the power conferred and to the general rules applicable to the construction of statutes. Generally if the act authorized is legislative in character the power is construed as discretionary; if executive it is usually held to be mandatory.

"The legislature has conferred upon the governing boards of the various political divisions of the state authority to determine whether a proposed local improvement is a public convenience or necessity. The determination of such question by the governing board is a legislative act, not subject to review by the courts. 'The act of the board of supervisors in determining whether a street shall be opened or closed, or widened or contracted, or otherwise improved, is a legislative act performed in the exercise of the power which has been conferred upon the municipality by the legislature to enable it to provide for the welfare of its citizens.' Brown v. Board of Supervisors, 124 Cal. 277, [57 Pac. 82]. 'The legislature having conferred upon the board of supervisors the power to open and close strects "whenever the public. interest or convenience may require," the determination by that board of the question whether the public interest and convenience require that streets be closed, is conclusive, and not open to review by the courts.' Symons v. San Francisco, 115 Cal. 555, [42 Pac. 913, 47 Pac. 453].

"It will probably be conceded that the determination of the question whether the public interest and convenience require that a bridge be constructed across a river is as fully a legislative question as that of opening or closing a street. A county or city cannot be compelled by the courts to bridge. every water-course crossed by its roads or streets, or any of them. In deciding to erect a bridge a public corporation is exercising discretionary power. Action or non-action in that regard can lead to no liability.' Coffey v. City of Berkeley, 170 Cal. 258, [149 Pac. 559].

"If the territory on both banks of the river to be crossed were wholly within the city of Redding, the determination of the trustees as to the necessity of a bridge would undoubtedly be conclusive; so that of the supervisors if the location were wholly outside the city. Is the rule different where the two boards are authorized to act jointly?

"If both boards had determined that public convenience required the construction of the bridge no one would contend that such determination was not conclusive. On the other hand, if both boards had determined that the public interest did not require the bridge, that determination would have been equally conclusive.

"The city trustees, in their legislative capacity, determined that the bridge was a public necessity. The supervisors, in their equal legislative capacity, determined that no such necessity existed in behalf of the county.

"Why are not the legislative determinations of such boards conclusive as to their respective jurisdictions, and by what authority is the determination of one board to be held superior to that of the other?

"In considering the question we must not confuse the authority conferred upon a board to construct a bridge with the duty of the board to keep the bridge in repair after its construction. Having in the exercise of their discretion, constructed and opened a bridge, thereby inviting the public to travel over it, the duty of the officers to keep it in good repair is mandatory. Having assumed the burden of maintaining the structure that obligation must not be discharged in a negligent manner.

"Again, the question of the construction by two boards. jointly of a new bridge must be distinguished from the obligation of each to maintain a bridge which they had by their voluntary agreement constructed jointly. The joint agreement to build implies an agreement for joint maintenance.

"Most of the cases cited by counsel for the plaintiff had to do with the repair or reconstruction or bridges rather than with the construction of new ones, besides, they are based upon statutes essentially different from ours.

"Thus, the Nebraska statute [Comp. Stats. 1909, c. 78, sec. 88] provided that if either county charged with the joint maintenance of a bridge should refuse to join with the other in making needful repairs, 'it shall be lawful for the other of said counties to enter into such contract for all needful repairs, and recover by suit from the county so in default such proportion of the costs of making such repairs as it ought to pay.'

...

"The law of Kansas [Gen. Stats. 1909, sec. 7309] provides that where a road is located on a county line, 'all expenses arising from the improvement of any portion of such road, shall be borne jointly by the counties. . . contiguous thereto.' It was held that one county could recover from the adjoining county for one-half the cost of making necessary repairs to a bridge on such a road. County of Brown v. County of Keya Paha, 88 Neb. 117, [Ann. Cas. 1912D, 790,