Stephen Gadd

Stephen Gadd

@docuracy.co.uk

Assistant Research Professor @camunicampop.bsky.social Technical Director, World Historical Gazetteer @whgazetteer.org Research Associate & GIS Consultant @ihr.bsky.social & @layersoflondon.bsky.social

646 followers182 following80 posts

Stephen Gadd
@docuracy.co.uk

🪄Historical Sea Routing is now much quicker to load, reload, and compute seasonally-plausible sailing routes, thanks to some behind-the-scenes browser magic. Find a 6500-mile return trip in under 1 second! 🛟 Do you have historical voyage data which might help with calibration? [1/3]

Stephen Gadd
@docuracy.co.uk

For sea-router calibration: 513 dated voyages from the Datini/Melis corpus (1379–1492) across galleys, carracks, brigantines and more. e.g. Venice → Mallorca, departing in a cog 19 Jun 1396: the router predicts 29 days, the source records 37. bsky.app/profile/did:...

Stephen Gadd@docuracy.co.uk

Companion to the Datini Letters map: a new Voyages explorer for the Melis archive. 3,393 Mediterranean ship records (1379–1492). Arcs coloured by predominant vessel type per route. Ports geocoded via @whgazetteer.org. docuracy.github.io/datini/viagg... #DigitalHumanities #DH #MedievalMed

Stephen Gadd
@docuracy.co.uk

🔔 A heavy church bell meant a heavy cart and a way capable of bearing it. Can the spread of bells >5cwt from their foundries serve as a proxy for pre-modern wheeled-transport networks, at least where navigable waterways can be ruled out? 1/5 #HistoricalGIS #EconomicHistory #TransportHistory

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Stephen Gadd
@docuracy.co.uk

In upland regions where pack-horses were the normal mode, heavy bells could not have travelled by that mode at all, which makes their presence there a stronger signal, not a weaker one. A bell in the Pennines is more interesting than a bell in the Home Counties. 4/5

Stephen Gadd
@docuracy.co.uk

This analysis would be impossible without the extraordinary work of the volunteers behind Dove's Guide for Church Bell Ringers, who have recorded bells across England and Wales and made their data freely available. A remarkable community resource 👏 5/5 dove.cccbr.org.uk #Bellringing #ChurchBells

Stephen Gadd
@docuracy.co.uk

🔔 A heavy church bell meant a heavy cart and a way capable of bearing it. Can the spread of bells >5cwt from their foundries serve as a proxy for pre-modern wheeled-transport networks, at least where navigable waterways can be ruled out? 1/5 #HistoricalGIS #EconomicHistory #TransportHistory

Stephen Gadd
@docuracy.co.uk

Two obvious objections. First, a parish desperate enough for a bell might have made a one-off effort (repairing a way, bridging a ditch) that left no permanent improvement. Presence of a bell is evidence of a journey, not necessarily of a usable way. 2/5 Waterways: doi.org/10.5284/1057...

Stephen Gadd
@docuracy.co.uk

Second, absence of bells tells us nothing: ways existed wherever people travelled, regardless of whether anyone at the destination wanted a five-hundredweight lump of bronze. The map shows where ways were used for this purpose, which is not quite the same thing. 3/5

Stephen Gadd
@docuracy.co.uk

✉️ Explore 145,000 medieval merchant letters as a live map: the correspondence network of Francesco di Marco Datini (c.1363–1412), spanning Florence to Barcelona to North Africa. Visualise routes, travel times & seasonality. docuracy.github.io/datini/ #DigitalHumanities #MedievalHistory

Stephen Gadd
@docuracy.co.uk

Update for anyone returning to this thread: I've added click-to-focus city filtering and full-state shareable links to the explorer. bsky.app/profile/docu...

Stephen Gadd@docuracy.co.uk

New in the Datini Letters explorer: click any city to focus on its correspondence routes. Shareable links capture the full state of the view. docuracy.github.io/datini/#mode... #MedievalSky #DigitalHumanities

Stephen Gadd
@docuracy.co.uk

New in the Datini Letters explorer: click any city to focus on its correspondence routes. Shareable links capture the full state of the view. docuracy.github.io/datini/#mode... #MedievalSky #DigitalHumanities

Stephen Gadd@docuracy.co.uk

✉️ Explore 145,000 medieval merchant letters as a live map: the correspondence network of Francesco di Marco Datini (c.1363–1412), spanning Florence to Barcelona to North Africa. Visualise routes, travel times & seasonality. docuracy.github.io/datini/ #DigitalHumanities #MedievalHistory

Stephen Gadd
@docuracy.co.uk

Fun piece by @justincolson.bsky.social and Werner Scheltjens. My job on this project is to turn messy medieval records into a tidy database so that my colleagues can more easily spot trends in fashion, industry, and commercial networks. theconversation.com/medieval-lon...

theconversation.comMedieval Londoners’ cheaply imported mass-produced Christmas gifts look surprisingly familiarWe often imagine medieval life as dull, dirty and short, with little in the way of material comfort or decoration. However, medieval Londoners were importing toys, treats and trinkets by the boatload ...

Stephen Gadd reposted

Gabriel Bodard
@palaeofuturist.bsky.social

Replying to @palaeofuturist.bsky.social

(4) Linking Knowledge Through Place: ISHI, WHG, and the Future of Gazetteer Collaboration, with @rmostern.bsky.social @docuracy.co.uk, Alexandra Loranna, Palak Vashist. Look at Institute for Spatial History Innovation & World Historical Gazetteer. Register to participate at forms.gle/dzSq2GibT17n...

forms.gleLinking Knowledge Through Place: ISHI, WHG, and the Future of Gazetteer CollaborationDescription: This activity focuses on advancing collaborative methods for historical place alignment across gazetteers and related datasets within the Pelagios community. It brings together members of...
Stephen Gadd
@docuracy.co.uk

Thanks, @drpda.bsky.social, this looks like a really useful source, as it includes dates and waypoints for a number of long-distance voyages. 👏 I'd love to get hold of Paula Martin's transcript, though: any suggestions of how I might do that?

Philip Allfrey@drpda.bsky.social

This is impressive work, I wish I had a use case for it! For a paleography course I took a decade ago we looked briefly at a journal of a 17th century Scots mariner. It's been digitised at collections.st-andrews.ac.uk/item/journal... Paula Martin made a transcription, but I don't know if it's online

collections.st-andrews.ac.ukJournal of Alexander Gillespie, skipper in ElieManuscript sailing journal of Alexander Gillespie, skipper in Elie, Fife, recording details of his trading voyages between 1662 and 1685.<br/> <br/> <br/>This journal records voyages undertaken by Ale...
Stephen Gadd
@docuracy.co.uk

🌍 Ports are now (optionally) shown on the eRutter to help with route picking. 🤔 They're currently fetched from @wikidatacommunity.bsky.social, but this would be a great use case for a @whgazetteer.org temporal API to filter out modern ports and highlight ancient ones.

Stephen Gadd@docuracy.co.uk

🪄Historical Sea Routing is now much quicker to load, reload, and compute seasonally-plausible sailing routes, thanks to some behind-the-scenes browser magic. Find a 6500-mile return trip in under 1 second! 🛟 Do you have historical voyage data which might help with calibration? [1/3]

Stephen Gadd
@docuracy.co.uk

🪄Historical Sea Routing is now much quicker to load, reload, and compute seasonally-plausible sailing routes, thanks to some behind-the-scenes browser magic. Find a 6500-mile return trip in under 1 second! 🛟 Do you have historical voyage data which might help with calibration? [1/3]

View full thread
Stephen Gadd
@docuracy.co.uk

🪄Historical Sea Routing is now much quicker to load, reload, and compute seasonally-plausible sailing routes, thanks to some behind-the-scenes browser magic. Find a 6500-mile return trip in under 1 second! 🛟 Do you have historical voyage data which might help with calibration? [1/3]

Stephen Gadd
@docuracy.co.uk

... 📱It works better on mobile devices now too, using Mercator projection instead of globe, and with an initially-minimised Options panel. The routes and all parameters used can be exported for use in other GIS applications. [2/3]

Stephen Gadd
@docuracy.co.uk

🌍 I've just published this here docuracy.github.io/Historical_S... for anyone to play with. Screenshots, code, and caveats at github.com/docuracy/His....

docuracy.github.ioSea Router
Stephen Gadd@docuracy.co.uk

🧭 Building a lightweight sea-routing graph for historical GIS & DH use cases beyond simple port-to-port hops. Edges are weighted for ~5km coastal preference. Aiming for serverless exploration of connectivity in historical maritime trade. ⚓️ #MaritimeHistory #HistoricalGIS #DigitalHumanities

Stephen Gadd
@docuracy.co.uk

🧭 Building a lightweight sea-routing graph for historical GIS & DH use cases beyond simple port-to-port hops. Edges are weighted for ~5km coastal preference. Aiming for serverless exploration of connectivity in historical maritime trade. ⚓️ #MaritimeHistory #HistoricalGIS #DigitalHumanities

View full thread
Stephen Gadd
@docuracy.co.uk

... I need yet to tune the weighting of various parameters, but it’s striking how the same principles that shaped trans-Atlantic triangular trade routes in the age of sail apply on a more local scale too: prevailing winds, swell, waves, and currents all make return routes diverge from outbound ones.

Stephen Gadd
@docuracy.co.uk

... Time of year makes a big difference too. Monthly-weighted graphs are switched and new routes computed in less than half a second, all within the browser.

Stephen Gadd
@docuracy.co.uk

🧭 Building a lightweight sea-routing graph for historical GIS & DH use cases beyond simple port-to-port hops. Edges are weighted for ~5km coastal preference. Aiming for serverless exploration of connectivity in historical maritime trade. ⚓️ #MaritimeHistory #HistoricalGIS #DigitalHumanities

View full thread
Stephen Gadd
@docuracy.co.uk

🧭 Building a lightweight sea-routing graph for historical GIS & DH use cases beyond simple port-to-port hops. Edges are weighted for ~5km coastal preference. Aiming for serverless exploration of connectivity in historical maritime trade. ⚓️ #MaritimeHistory #HistoricalGIS #DigitalHumanities

Stephen Gadd
@docuracy.co.uk

... using this graph of interconnected H3 (Hexagonal Hierarchical Geospatial Index) cells, I've computed and plotted a speculative historical sea route from Kilcolgan Castle to Faxfleet in under 2 seconds, all running in the browser. No server infrastructure or internet connection needed! ⛵

Stephen Gadd reposted

World Historical Gazetteer
@whgazetteer.org

Want to work with the WHG team? The Institute for Spatial History Innovation @ Pitt is hiring a full-time Research Associate to be the Digital Data Specialist & Managing Editor of World Historical Gazetteer! Learn more & apply by July 11: bit.ly/4kAknki @rmostern.bsky.social @docuracy.co.uk

bit.lyJob Opportunity - Research Associate at Institute for Spatial History Innovation | World History Center | University of PittsburghThe University of Pittsburgh's Institute for Spatial History Innovation (ISHI) is currently accepting applications for a full-time Research Associate to act as the Digital Data Specialist. The selecte...

Stephen Gadd reposted

Hobnob Press
@hobnobpress.bsky.social

Discover 17th century travel through the eyes of John Walker in our new release. Edited by Anthea Jones. www.hobnobpress.co.uk/books/p/john...

hobnobpress.co.ukJohn Walker's Commonplace Book: A Traveller in the 1670s, edited by Anthea Jones — Hobnob PressTravelling for pleasure in the 1670s required plenty of stamina. John Walker, a well-to-do country gentleman in his early thirties, rode many miles on horseback through England, Wales and Scotland, an...
Stephen Gadd
@docuracy.co.uk

👇Results from my latest version of desCartes, a hybrid machine learning system for detecting roads on old maps. Its 0.76 IoU score for roads is 31% better than the closest benchmark. 🤯 Preprint forthcoming on arXiv.

Stephen Gadd reposted

James Baker
@jwbaker.bsky.social

The 2025 Richard Deswarte Prize in Digital History celebrates the best of digital history internationally. You have until 30 May to nominate your work or work you love. Please consider doing so. ihrdighist.blogs.sas.ac.uk/2021/12/the-... #dhist

ihrdighist.blogs.sas.ac.ukThe 2025 Richard Deswarte Prize in Digital History - Digital History Seminar**SUBMIT HERE BY 30 MAY** Richard Deswarte (1965-2021) was one of the founding convenors of the Digital History seminar at the Institute of Historical Research (IHR), University of London, an advocate...

Stephen Gadd reposted

Alexis Litvine
@alexislitvine.bsky.social

Really enjoyed working on this with Stan Hinton and would love to get some feedback on methods and findings from anyone out there. All criticicsm welcome, this is what WPs are for!

Cambridge Working Papers in Economic and Social History@cwpeconhist.bsky.social

❕New WP from @alexislitvine.bsky.social and Stan Hinton❕ 𝐁𝐞𝐲𝐨𝐧𝐝 𝐬𝐞𝐜𝐭𝐨𝐫𝐬. 𝐀 𝐬𝐮𝐛𝐬𝐞𝐜𝐭𝐨𝐫𝐚𝐥 𝐚𝐧𝐚𝐥𝐲𝐬𝐢𝐬 𝐨𝐟 𝐡𝐢𝐬𝐭𝐨𝐫𝐢𝐜𝐚𝐥 𝐨𝐜𝐜𝐮𝐩𝐚𝐭𝐢𝐨𝐧𝐚𝐥 𝐝𝐚𝐭𝐚 𝐚𝐧𝐝 𝐭𝐡𝐞𝐢𝐫 𝐫𝐞𝐥𝐚𝐭𝐢𝐨𝐧 𝐭𝐨 𝐞𝐜𝐨𝐧𝐨𝐦𝐢𝐜 𝐠𝐫𝐨𝐰𝐭𝐡

Stephen Gadd reposted

Cambridge Group for the History of Population & Social Structure
@camunicampop.bsky.social

📣New blog post alert! 📣 Who had access to common land in the past, and how extensive were common rights? Our latest blog post by Leigh Shaw-Taylor demonstrates that it was not such an open system as we might assume, even before enclosure... www.campop.geog.cam.ac.uk/blog #skystorians

campop.geog.cam.ac.ukThe Cambridge Group for the History of Population and Social Structure, Cambridge Top of the Campops: 60 things you didn't know about family, marriage, work, and death since the middle ages

Stephen Gadd reposted

Margot Finn
@eicathomefinn.bsky.social

Even when the Bayeux Museum closes for renovations in September, you can access the Tapestry online here. A treat for #Skystorians

Isabelle Marie@isabellemarie.bsky.social

Explorer la Tapisserie de Bayeux en ligne. www.bayeuxmuseum.com/la-tapisseri...

bayeuxmuseum.comExplorer la Tapisserie de Bayeux en lignePour la première fois, vous allez pouvoir explorer librement la totalité de la Tapisserie de Bayeux avec une qualité d'images exceptionnelle