The gist of relators' claim to mandamus is that, under the contract plans and specifications, they were compelled to remove 4248 cubic yards of rock and dirt below the line of the crown of the road, and then back-fill the excavation with suitable material; therefore, it was a ministerial duty of the division engineer to certify that excavated yardage at 44c *Page 47 per cubic yard in favor of relators to the Commission, and the ministerial duty of the latter to pay therefor. The opinion is based on the contract, section 32 of the Standard Specifications and the cross-section appearing on the plans, and correctly holds that the contractors undertook to complete the grading and receive pay therefor on the basis of measurements determined by the contour of the crown of the road. The opinion correctly holds further that the final estimate of the division engineer of work done does not estop the Commission from refusing to pay for items therein contained, which are not authorized by the contract, specifications and plans. Otherwise, the Commission would be a "rubber stamp", and would be bound by what the engineer conceived the contract to be. No such power was ever intended to be lodged in the engineer. In the Commission is placed plenary power in the construction and maintenance of state roads by the act creating it, defining its powers and duties, and not in its agents, servants and employees. In the brief filed for rehearing it is argued that Blackwood, claimed by relators to be the engineer on the project, ordered relators to excavate the material here in controversy, when he called Black's attention to the Standard Specifications. Blackwood says he was not the engineer on the job, that he was the inspector, and did not as such direct; that his duty as such was to supervise the completion and see that any defect was remedied; that when the contract and plans are departed from, it is the inspector's duty to have corrections made. His statement is to this effect, that the excavation here sued for was not done at his direction. If the excavation was within the contract, as here claimed, why should the inspector be asked if that work should be done? Was it then a matter of doubt under the contract? The contract, Standard Specifications and plans speak for themselves. They form the contract, what shall be done by the contractor, and when done in accordance therewith what the Commission shall pay. The issue here is whether that contract includes the excavation sued for as unclassified, and whether the excavation was directed to be done by the Commission through its engineer, and, as above stated, falls within that contract. It must be remembered *Page 48 that this is a mandamus proceeding, and not an ordinary suit at law for breach of contract; and as pointed out in the Court's opinion, the relators must show a clear legal right to have a ministerial act performed; or if respondent has discretion to do the act required, then it must be clear that the refusal is arbitrary or wilful. The most that can be said of relators' claim under the contract and the evidence is that their right to have the engineer make a final estimate so as to include the 4248 cubic yards involved and certify the same to the Commission, and to require the Commission to pay for it as unclassified material, is of such doubt that the extraordinary and harsh remedy of mandamus will not lie. Had the case been tried by a jury and questions of fact determined by it and under proper instructions, we would not be disposed to disturb a finding either for relator or the Commission. InDraper v. Anderson, 102 W. Va. 633, cited in the opinion and dissent, the refusal of Anderson, the division engineer, to certify the yardage removed by the contractor under and covered by his contract was the result of a controversy between the contractor and West, the engineer in charge of the work, which degenerated into a fight between them, West receiving a severe trouncing. The refusal to certify was arbitrary, and the motive apparent. That case did not involve a substantial controversy of fact.