In its broadest sense, it undoubtedly includes a street railroad, and every other kind of a road or way on which rails of iron are laid for the wheels of 'cars to run upon, whether propelled by steam, electricity, horse, or other power, carrying light or heavy loads of freight or passengers, or both. 2 Bouv. Law Dict. tit. ''Railroads.'' In its technical sense it does not apply to street railroads