I apologise I cannot share with you the map I am referring to by Jacob Millerd, of Bristol. I am thinking of a bigger, more detailed version of the many he produced, but this one from 1671 will give you an idea.
The river Avon winds through the city, and is dotted with a wide range of craft, from rowing boats with cows and canons to full rigged sailing ships. But the pattern is far from random. the big ships moored further downstream, to save them having to manevre whereas the smaller boats, such as the welch farmers boats moored on Welsh Back.
The big version also had a few ducks and what I assumed to be seals, apparently a long way inland, but they seemed to be dog paddling and had ears. I was bemused until I found a story about a couple having an argument near Bristol Bridge. He threatened to throw their baby into the river; she thought he did and jumped in. Then comes the interesting bit – locals launched their water dogs as was usual practice.
I looked at the map again. Could these seals be water dogs? Then I realised, they were only upstream on the map, where the old waterside houses were, not round the quays and warehouses. One of the seals had a t-bar on its back. A rescue dog. It has to be. In the centuries before the quays were properly constructed, the waterside was a long slope of mud, so many people fell in, and if this was between boats, was incredibly difficult and dangerous trying to rescue them, day or night.
These old maps are brilliant, full of character and life. Sometimes I feel like I can wave to people in their back gardens. More so than the text, they tell us so much about the old city, how people saw it, how they used the streets. and more than just a picture, because these maps are lots of pictures, they must have taken an immense amount of walking about, thinking, looking, they required an understanding of the city, its dimensions and activities that we can only dream of today.
As a writer of walking books, I have spent a lot of time drawing maps, but this is in the modern age, with nice wide open spaces, clean lines of sight to get a good idea of what I am looking at. and plenty of affordable paper to jot stuff down on. Drawing maps is a great mental exercise. It is a wonderful way of exploring your environment and thinking how things fit together. How a city works.