In addition to the rights and powers conferred on railroad corporations by their charters and the laws of this state, the directors are authorized and empowered, by and with the consent or approval of a majority of the stockholders, to cause to be issued and executed, bonds or other evidences of indebtedness whenever deemed expedient and to secure the payment of the indebtedness by a mortgage or deed of trust or other encumbrance of all or any part of their charters, franchises, income, rights-of-way, materials, roadbeds, rails, railroads built and to be built, rolling stock, lands, and other corporate properties owned or afterward acquired.