How did the streetcars in Milwaukee cross the Wisconsin Avenue bridge over the Milwaukee River ?

 I saw several pictures online of the Wisconsin avenue bridges that spanned the Milwaukee river:

  In some of them the electric streetcars are visible:

The earlier bridge (shown about 1900) pivoted or turned to let ships through.  But what happened with the  wires (both the overhead DC wires and the rails used as the ground connection) when the bridge opened ?  Unfortunately none of the pictures has the detail to show these connections.

My hope was that the streetcar driver had to gun it and coast over the bridge but I doubt that that would have been tolerated :)

The later bridge (built in the 1900-1909 period) got rid of the pivot/island to open up in the middle:

But there again the wires aren't visible, however there are two inverted "U" supports which appear to be for the streetcar wires.

It must have been a hassle for all involved when a ship had to pass.

I was at the dedication of the current bridge in the 1975 (I will have to dig up the pictures I have and post them).  By then the streetcars and their replacement trackless trolley buses were long gone so there were no wires required anymore.

Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm