Section 1. Be it enacted, &c., That any passenger railway company, incorporated under the act to which this is a supplement, shall have and is hereby granted power, by its officers and servants, to ascertain and define such route as they may deem expedient, over, upon and along any bridge or bridges, other than steam railroad bridges, on the route of such railway company, not however exceeding sufficient width for two tracks, to be laid down, on, over and along such bridge, and thereupon, on, over and along such bridge or bridges, to lay down, construct and establish a track or tracks for its use in the transaction of its business, and thereupon to use the same in its general business. This act shall include all bridges, other than steam railroad bridges, whether owned by bridge corporations or individuals, an approach to which is within the corporate limits of the city, within which the route or proposed route runs, and whether such bridge spans a stream or river navigable or otherwise, and also all bridges, other than steam railroad bridges, extending over any stream from cities of the second class to cities of the third class; and this act shall also include all bridges, other than steam railroad bridges, on which a track or tracks for a passenger railway company is or are now laid or used, and shall also include all passenger railways now in occupation or use of any such bridge or bridges: Provided, That before such passenger railway company shall enter upon and use any such bridge in the laying of tracks and use of the same or the use of tracks now laid upon any bridge, they shall make, or secure by a bond as hereinafter stated, ample compensation to the owner or owners thereof, for such occupation and use of said bridge.