"there was a painting by Guardi"

Francesco Lazzaro Guardi (1712-1793) was an 18th century Venetian artist. He is particularly well known as a painter of the large-scale, highly detailed landscapes known in Italian as vedute.

 

'Doge's Palace in Venice' (2nd half of 18th century)
Public Domain'Doge's Palace in Venice' (2nd half of 18th century) - Credit: Francesco Guardi