It seems to be conceded by the parties that the .ruling of the court on the demurrer to the sixth count of the •complaint fully presents the questions to be settled by this appeal; and, as counsel for appellant have limited their argument to the assignment of error predicated on this ruling, the court will only treat the questions thus presented.

(1) It is well settled where one person, in order to protect his own interest, pays a debt for which another is legally liable, the law implies an assumpsit on the part of the latter to the former. — Beard v. Horton, 86 Ala. 202, 5 South. 207; Ledger Pub. Co. v. Miller, 170 Ala. 437, 54 South. 52; Walker v. Smith, 28 Ala. 562; 27 Cyc. 833-836. And a request will be implied where the consideration consists in plaintiff having been compelled to pay that for which the defendant was legally liable. — Nutter v. Sydenstricker, 11 W. Va. 535.

Therefore, if the defendants were legally liable for the repairs made on the drain, and the plaintiff, in order to comply with its statutory duty and protect its own interests, caused the repairs to be made and paid therefor, under the principles above stated, it could maintain an action of assumpsit for money paid for defendants at their instance and request. — 27 Cyc., supra.

(2, 3) Before the plaintiff would be entitled to recover, it was incumbent on it to show that the defendant was liable by *239 contract either express or implied for the repairs on the drain which the plaintiff alleges it caused to be made and paid for.— 2 R. C. L. 747, § 6. Such contract will be raised by implication of law if the defendants were under legal duty to make the repairs and the plaintiff, in order to conform to its statutory duty and protect itself, caused them to be made and paid the expenses incident thereto. — 2 R. C. L. 749, § 8. So, also, if the repairs were made necessary by the tortious conduct of the defendants and defendants were benefited by the commission of the tort.— Judson v. Eslava, Minor, 71, 12 Am. Dec. 32.

The plaintiff undertakes to bring the case within these principles by the averments found in the sixth count of the complaint that the defendants, at the time of opening the drain, were engaged in the business of plumbing in the city of Mobile, and previous thereto had applied for and obtained from the city authorities a license to engage in this trade under its ordinances and regulations, providing: “All persons who shall engage in the business of plumbing in the city of Mobile shall, before receiving license therefor, furnish to the plumbing inspector satisfactory evidence of their ability and willingness, or the ability of their employees to do the work in accordance with the rules and regulations prescribed in an ordinance entitled ‘An ordinance to regulate connections with the sanitary sewers of the city of Mobile, Ala.,’ and shall take out a license, for which he shall pay at the rate prescribed annually by the general council.”

That the ordinance regulating sanitary connections provided: “In opening trenches on any street or public way, paving or ballast must be removed with care, the side of the trench sheeted or braced when directed by the superintendent of sewers, or other duly authorizd inspector; gas and water pipes must be protected from injury, and the trench must be inclosed and lighted at night, and every .precaution must be taken to prevent injury to the public during the progress of the work. Whenever it shall be necessary to disturb a drain, it must not be obstructed without the direction of the superintendent of sewers or an authorized inspector; when a trench has been opened, or when a drain has been disturbed in refilling the said trench and in replacing the dirt, the back-filling shall be thoroughly rammed with rammers weighing not less than twenty pounds, and the paving or ballast replaced in good condition and to the satisfaction of the superintendent of sewers, or an authorized inspector, within forty-eight *240 hours after the back-filling of the trench; and any neglect of this rule shall be sufficient cause for the revocation of the drain layer’s license and permit, and any settlement over the drain on any street or public way within one year after the laying of the drain, shall be repaired at the expense of the plumber or drain layer doing said work.”

(4-6) In the light of the duty resting upon municipal corporations to maintain their streets in reasonably safe condition for public travel, it is not unreasonable to say that the corporation, as a prerequisite to the issuance of a license or permit to a class of artisans who, in the prosecution of their business, are called upon to make excavations that disturb the surface of its streets rendering their use hazardous to the public, may require the street to be restored to its natural and reasonably safe condition, and that the work of restoring the street be guaranteed for a reasonable time. — Hill v. City of St. Louis, 159 Mo. 159, 60 S. W. 116. Such liability, however, would depend upon contract between the parties, either express or implied from the transaction, and necessarily a prerequisite to the issuance of the license or permit to open the drain. Such liability cannot be arbitrarily imposed by ordinance, and independent of contract.

(7) Municipal corporations are creatures of the Legislature of the state, delegated with limited legislative authority, and may adopt measures, within that authority, having the force of law. — Dillon, Municipal Corporations (5th Ed.) 573. But in the adoption of ordinances they must conform to the Constitution; and any ordinance that arbitrarily fixes liability on the citizen in the prosecution of his lawful business, in the absence of contract, wrong, fraud, or neglect on his part, denies due process of law and is void. — Zeigler v. S. & N. Ala. R. R. Co., 58 Ala. 594; Elliott on Roads & Streets, § 517.

(8, 9) The only prerequisite to the issuance of a license to plumbers provided for in the ordinances set out in the complaint is that the person applying therefor “shall, before receiving a license therefor, furnish to the plumbing inspector satisfactory evidence of their ability and willingness or the ability of their employees to do the work in accordance with the rules and regulations” prescribed by the ordinances of the city, and “pay at the rate prescribed annually by the general council.” There is no suggestion that the applicant will, by the acceptance of such license, assume liability in excess of that imposed by the *241 general law of the land. There is no contention that there is an express guaranty, but the contention is that the law will imply one from the acceptance of a license; but the circumstances here do not warrant the conclusion that the defendants assumed any such liability.

The provision in the ordinance under which appellant seeks to establish the liability of the defendants, when considered as a whole, is subject to the reasonable construction that it does not impose liability in the absence of negligence, and this construction will be adopted in order to uphold it. It provides: “When a trench has been opened, or when a drain has been disturbed, in refilling the said trench and in replacing the dirt, the back-filling shall be thoroughly rammed with rammers weighing not less than twenty pounds, and the paving and ballast replaced in good condition and to the satisfaction of the superintendent of sewers, or an authorized inspector, within forty-eight hours after the back-filling of the trench; and any neglect of this rule shall be sufficient cause for the revocation of the drain layer’s license and permit; and any settlement over the drain on any street or public way within one year after the laying of the'drain, shall be repaired at the expense of the plumber or drain layer doing said work.”

The manifest purpose of the provision was to make' the plumber or drain layer liable for negligence to the penalty of revocation of the license and the cost necessary to make the repairs.

The ruling of the circuit court was free from error, and the judgment is affirmed.

Affirmed.