The Thames at Westminster Stairs (1630s) by Claude de Jongh
Halley Docherty (Reddit user halz) has created 15 more stunning images of London by mashing up old paintings and placing them in their modern setting. You can view the original set of images here.
View of London Bridge (1632ish) by Claude de Jongh
Gin Lane (1751) by William Hogarth
Trafalgar Square (1837ish) by James Pollard
Hatchetts – The White Horse Cellar, Piccadilly (1850ish) by James Pollard
Waterloo Place (1886) by Filippo Baratti
North Country Mails at the Peacock Islington (1821)by James Pollard
View of the Strand from the Corner of Villers Street (1830-40) by George Sharf
A Sunset with a View of Nine Elms (1750-65) by Samuel Scott
Newington Turnpike and a View of the Elephant and Castle (1825) by Gideon Yates
Elephant and Castle, Newington (1826) by Samuel Jones
View of Hammersmith Broadway and Queen Street (1831–1838) by James Pollard
A View of Fulham from Putney with Old Fulham Bridge, All Saints Church and the Bridge Toll House (1730ish) by Joseph Nicholls
Old Walton Bridge (1754) by Canaletto
Old Walton Bridge [Detail] (1754) by Canaletto
You can read about the history of each image from the imgur page here.
Looking at these superimposed views .the new has lost beauty and become something to lookaway from rather that look at .
Old paintings of London I look at the bridges retains pleasing forms of building .that allow you to look back to an era and imagine .who could ever think that a design of the tower of London could be built on a bridge and lived in .just to look out of the window and see the changing tides below you .and to gaze at river traffic .and not to be affected by time .