All railroad companies incorporated under the laws of this state, having a terminus upon any navigable river bordering on this state, shall have power to own for their own use any water craft necessary in carrying across such river any cars, property or passengers transported over their lines, or transported over any railroad terminating on the opposite side of such river to be transported over their lines: Provided, that no right shall exist under this act to condemn any real estate for landing for such water craft, or for any other purpose. And this act shall only apply to such railroad companies as own the landing for such water craft: Provided, also, that nothing in this act shall be held to impair or affect any right or privilege granted any ferry company incorporated under the laws of this state; and that all the powers and rights herein granted said railroad companies shall be subject to whatever rights and privileges may have heretofore been granted to any ferry company in this state, and that nothing in this act shall prevent said railroad companies from being subject, in the use of such water craft, to all laws of the state regulating ferries now in force or hereafter to be in force: And, provided, further, that nothing in this act shall be held or construed to authorize any railroad or railway company doing business under any charter granted by this state, to consolidate with any railroad or railway company out of this state, so as to form one continuous line of railroad, or otherwise to alter, modify or repeal any provision of any such charter granted by this state; or to impair the rights of this state as now reserved to it in any such charter.