The Mackinac Bridge over the Straits of Mackinac in Michigan - Photo: Lucy Gridley - Vintage Bridge Postcard United_States the "educated" porpoises perform their

the "educated" porpoises perform their feats

On front: Bakers Haulover Birdge

This Classic photo was taken in 1923

There is some evidence of water damage along the bottom half of the pages

1947 from Blair

The Mackinac Bridge over the Straits of Mackinac in Michigan - Photo: Lucy Gridley - Vintage Bridge Postcard United_States the "educated" porpoises perform theirOn front: The Mackinac Bridge over the Straits of Mackinac in Michigan On back: The Mackinac Bridge The New Northwest Passage spanning the Straigts of Mackinac in Michigan, The Water Wonderland. The greatest tourist attraction in the Midwest. Unmailed: Condition: excellent Publisher: Colourpicture Publishers Inc. Color print