John Rennie may be:

John Rennie - Biography from Significant Scots.
John Rennie - Brief biography with portrait from the BBC historic figures.
Meta Description: [ Rennie's work on canals, aqueducts, bridges and dockyards mark him as one of the greatest engineers of his age. ]
John Rennie: Enlightenment Engineer - Biography by Roger Donway. Highlights Rennie's construction of the new London Bridge.
Meta Description: [ London Bridge—as every child used to know—was falling down. John Rennie was the man brought in to replace it. ]
Wikipedia: John Rennie - Biography and portrait, projects list and related links.