It is true that a professional engineer called by the claimant opined that the increased flow caused erosion along the retaining wall after October, 1959 when the new drainage system began operating and that the erosion-weakened wall finally collapsed under extra "scouring" from the flow of water during "Hurricane Donna" on September 12, 1960. However, his testimony was based solely on his professional knowledge of the consequences which might follow as a result of an increased flow, but since he had never seen the wall prior to its collapse; did not know the height of the stream; the base on which the wall was resting, its location or depth; whether there were any tie rods connecting the wall and the building and when asked to reconstruct erosion was unable to do so, his testimony could properly have been rejected by the trial court as depending too much on speculation and surmise ( Bianco v. New York State Thruway Auth., 15 A.D.2d 695). Finally, there is evidence that contrary to claimant's contention collapse was caused by the fact that the wall was not sufficiently reinforced to withstand the increased hydrostatic pressure resulting from the heavy precipitation associated with "Hurricane Donna". On this state of the record we find no basis to disturb the trial court's determination ( Eason v. State of New York, 280 App. Div. 358).
The liability found in this case flows from the proof contained in this record. (Cf. Bianco v. New York State Thruway Auth., 15 A.D.2d 695.) The State raises no other questions in regard to its liability in this case and, accordingly, we consider no other questions.