Notwithstanding the breadth of the language of the agreement that all loss or damages from unforeseen obstructions and difficulties and from delay, were to be borne by the contractors, it-.is clear that the delay from the city’s failure to obtain complete right-of way was not in the class of difficulties and delays -which were in the minds of the parties, for the agreement itself was based on the assumption by both parties that the complete right of way had been secured'so that the work could be begun at any point and proceed without intei’ruption.

For- the same reason .the provision for extension of time only on written assent by the director of public works is not applicable.

There was therefore no breach of the agreement by the plaintiffs .which prevented them from recovering, and the authorities are clear that they were not bound to abandon the work or *135to be taken as having waived the delay caused by the city. While they might have abandoned it they had the option to continue and claim the damages caused by the city’s fault.

The dispute as to grading was one of amount alone. The director of public works might have settled the amount conclusively by measuring and certifying it, but he did not do so. It was therefore a question for the jury.

Judgment affirmed.