A railroad corporation whose road is crossed by a highway or other way within the corporate limits of any city or town on a level therewith, shall, at its own expense, so guard or protect its rails by plank, timber or otherwise as to secure a safe and easy passage across its road and if, in the opinion of the proper municipal authorities thereof, any subsequent alteration of the highway or other way, or any additional safeguards, are required at the crossing they may order the corporation to establish the same.