Any company may, in the construction of its railroad, cross the railroad of any other company or connect with the same. If it cannot agree with such other company as to such crossing or connection, the Commissioner of Transportation may determine the place and manner of such crossing or connection, after reasonable notice to the companies in interest to appear and be heard in relation to the matter, and may make such orders as to bridges, abutments, piers, tunnels, arches, excavations, retaining walls, embankments and approaches as he judges necessary; but no railroad shall cross any other railroad at grade, except for the purpose of connecting therewith, when the avoidance of a grade crossing is practicable, and the commissioner shall decide the question of practicability.