Section 103. A railroad corporation whose railroad is crossed by a public way at the same level 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 railroad; and if, in the opinion of the county commissioners, any subsequent alteration of the highway or other way or additional safeguards are required at the crossing, they may make a decree ordering the corporation to establish the same as provided in section one hundred.