It does seem odd to head for Europe’s flattest country for a project on contour lines, but this morning found me sitting in Rotterdam City Archives waiting for a map to be brought to my table, it’s one I’d seen online: drawn by Ancelin in 1697, but as he’d published nothing about it (and it had been pretty much forgotten) I wasn’t sure it had a place in my story. Then – as two grown men struggled with the door, a huge folder grasped between them – I had that feeling of hitting gold.
This map is exceptional in so many ways, hand drawn, with lines of pencil, ink and coloured washes, it depicts a section of the river Maas with: colour coded isobaths (submarine contours), soundings tracked as number series traversing the river, triangulation lines ascertained from heights such as the “Franken Kirk”. And strangely modern features: nothing appears in relief, no pretty ships, churches or windmills, the cathedral – all the buildings – are drawn from a bird’s eye view.
Images courtesy of Rotterdam Stadsarchief
On Friday I’m going to see another map 100 years older than this one, but at present this has to be the most beautiful and incredible contender for the very first use of contour lines.