The first Glasgow directory was published in 1783 by John Tait. This image is taken from a facsimile reprint published in 1871 by Robert Forrester. Page 73 lists arrivals and departures at the Glasgow Post Office, in the middle part of the week.
As this list shows, there was a considerable expansion in the network of post towns in Scotland in the 18th century, and delivery was aided by improvements in roads and bridges. But the mail was normally carried by post boys, on a horse or on foot, and services were unreliable.
Reference: Mitchell Library, GC 914.14351
Reproduced with the permission of Glasgow City Council, Libraries Information and Learning
directories, family history, foot post, genealogy, horse post, John Tait's Directory, post boys, Post Office, postal services