This appeal is by the plaintiffs in an issue to determine the amount of damages which they have sustained by the taking of their land by the defendant under its right of eminent domain. The first assignment, which charges error in the order of the court below overruling exceptions to a bond filed, is in palpable disregard of rule 26. We cannot learn from it the character of the bond filed, or what exceptions were taken thereto. Assignments of error constitute an essential part of the pleadings before us, and as such must be so complete in themselves as not to require reference to other parts of the record presented for our consideration: Cessna’s Est., 192 Pa. 14; North Mountain Water Supply Company v. Troxell, 223 Pa. 315. We gather from the printed argument of counsel for appellants that the bond referred to in the first assignment was to secure the payment of damages for land taken by the appellee, and that the exceptions to it set forth that the appellee had made no effort to agree with the owners of the property as to the amount.of damages sustained. But there is an admission in the same printed brief that an ineffectual effort had been made by the appellee to agree with Mrs. Burkhard, one of the joint owners. Upon failure to agree with her, the Only course open to the water company was to file its bond. Aside from this, however, the *372filing of the bond was in itself evidence of the inability of the parties to agree: Wadhams v. Lackawanna & Bloomsburg R. R. Company, 42 Pa. 303; Burkhard v. Pennsylvania Water Company, 234 Pa. 41. The first assignment of error could not, therefore, be sustained, even if it were in proper form. The second assignment is without merit, and the remaining six call for no discussion. It is sufficient to say that the questions put to L. E. Chapin, the hydraulic engineer called by the plaintiffs, were properly disallowed after he had said, on cross examination and in reply to a question by the court, that he did not have, and did not pretend to have, any knowledge of the market value of the land taken or of the values of lands in its vicinity.

Judgment affirmed.