Plaintiff brought this action to recover damages sustained as a result of defendant's alleged trespass. The complaint, served on July 20, 1960, alleged that plaintiff was the owner of certain premises known as 509/511 Avenue of the Americas (6th Avenue) and 103/105 West 13th Street, in the Borough of Manhattan, City of New York. Plaintiff commenced construction of a 16-story apartment building on these premises. The plaintiff further alleged that on or about March 2, 1960, while excavating the property for the purpose of driving piles for the foundation of the new structure, plaintiff discovered an encroachment allegedly belonging to the Sixth Avenue Subway which had been completed in 1939. The encroachment was located below ground at a depth of about 30 feet. Plaintiff alleged that it was damaged in that: (1) new plans had to be drawn, redesigning the substructure and foundations, in order to take the encroachment into account; (2) it suffered a deprivation of the use of part of its basement; and (3) the work became more expensive.