construct, complete and place in position according to tbe specifications attached thereto, a wooden inlet pipe to be located at the water works, Erie, Pa., and for which they agreed to pay Linn the sum of $3,625. The parties, having afterwards ascertained that the space between the piers or lower cribs, in which the wooden tube was to be located, was insufficient to allow the insertion of a tube of the size required by the specifications, agreed, on the 30th of June, 1884, that the size of the tube should be reduced to four feet three inches inside diameter. It appeal’s that John Dunlap was a partner of Linn and jointly interested with him in this work. It also appears that the parties entered into the contract in a mutual misapprehension of the condition of the space between the piers. They supposed that it was free from obstructions but on removing the roof it was found to be filled with clay, sand, sticks, and other substances which had been forced into it and had become compact and difficult to excavate. When this condition was discovered the contractors refused to proceed with the work unless the commissioners would agree to compensate them for excavating and removing the material so accumulated. It was readily recognized by both parties as a condition at variance with their former understanding of the situation, and for which no provision was made in their contract. The commissioners then directed the contractors to proceed with the work and agreed to pay them for the additional labor made necessary by this unexpected condition. The original contract as modified by the agreement of June 30fch respecting the size of the tube, was completed and the extra work was done, to the satisfaction of the commissioners. The claim of the contractors for extra work is now resisted on the ground that the action of the commissioners with reference to it was informal, and was not entered by their secretary upon the books of the water department. It is conceded by the learned counsel for the appellants that the fourteen specifications of error really raise but one question, and that is whether the agreement in respect to compensation for extra work is binding upon the corporation.
It is settled by the verdict that the parties were mutually mistaken as to the condition of the space between the piers and that upon the discovery of their mistake it was agreed between them that the excavation and removal of the material accumu