This model meets multiple model criteria for object proposed in this challenge. First, it is a movable bridge. Second, It is a unit that can be linked in the Chain Reaction Models.
I have also decied to use this and some other new models in an on-going project, I have named:
A Chicago Celebration
This chain reaction project will link together moving models inspired by the Art and Industry of Chicago.
For more information check my web stie. For Now, here is the new model:

The model is inspired by the many moving bridges that span the Chicago River designed to allow sail boats to procede to Lake Michigan.
The working model is viewable on YouTube:
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