A selection of signs in the National Museum of Scotland in Edinburgh, the largest one of which pertains to the parcels service provided by Edinburgh Corporation Tramways, which had its own sorting office, and which used boys as runners to collect/deliver the packages.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/24049533@N00">Bruce McAdam</a>
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/bruce_mcadam/5989593775/">Edinburgh trams</a>