The hairy banker

The architecture in this part of Glasgow city centre - St Vincent Place - is amazing.
This chap with the impressive beard who adorns the front door of the Clydesdale Bank, is Father Clyde, and he represents the river which made Glasgow prosperous.
Charles Grassby sculpted the impressive figure in 1874.
I don't know what the Latin phrase 'litore ad litus' means. Maybe someone can help.