Yesterday afternoon the first passenger train was run through the new Cambridge subway from the Park street terminal to the Harvard square station. The train consisted of three of the new style cars and the third rail was electrified throughout its entire length to provide power for the run.

The party to make the trip consisted of several of the officers of the Boston Elevated Railroad Company and members of the Transit Commission. The time of the trip was about fifteen minutes, including short stops at Kendall and Central squares. It is expected, however, that the running time when the subway is in actual operation will be about eight minutes.

While it is impossible to set any definite date for the opening of the subway to the public, the work is now so far along that it will probably not be many weeks before it will be ready for use.

The cost of the undertaking, it is estimated, will be about $12,000,000. The Boston portion of the tunnel has been built by the Transit Commission of the city of Boston and will be leased by them to the operating company, the Boston Elevated Railroad. The tunnel in Cambridge, however, has been constructed by the railroad company and is owned by it.