What a fantastic image of a Clutha ferry bringing passengers into the city centre. It can be seen approaching the first Caledonian Railway lattice bridge that linked the Central Station on the north bank of the river Clyde with Bridge Street Station on the south bank. Built by Sir William Arroll in 1878. The bridge supporting piers were cast iron caissons sunk onto the river bed, in matching pairs, and then filled with concrete to give a solid base upon which to build the granite stonework above the water line. If you look closely you will see a steam engine pulling carraiges across the bridge! The bridge steelwork was removed in 1967 but the supporting piers remain in place to this day, a testament to outstanding Victorian engineering.