Tithe H3
Layers
Tap a parcel for its details.
The parcels of the David Stewart estate plan, traced through the 1841 tithe map onto today’s map, with an OS grid reference and H3 hexagons for each.
The parcels
| Light | Plan no. | 1841 plot | Occupier (1841, as entered) | Grid ref | H3 res 8 |
|---|
Data: parcels CSV · GeoJSON · 1841 plots inside the plan boundary (CSV)
How it was made
- The plan. The David Stewart survey of the Bute Glamorgan estates, plan of Cedfin alias Ty Mawr (the library dates the survey c.1822–24). Its parcel numbers were read by eye from a phone image. The figures run 1 to 45; the ones that look like 50–59 are written with an old-style 3, so we read them as 30–39. Numbers 1–4 in the homestead group and number 18 could not be read; those parcels are shown as “not read”.
- The 1841 tithe map. Plan of the parishes of Landough, Cogan and Leckwith, Edward Edmunds, 1841, scale 8 chains to an inch (National Library of Wales). Its plot outlines were traced from the plot-number positions in the library’s apportionment index. Where a plan parcel and a tithe plot are the same field, the clearer tithe outline is used; otherwise the plan’s own outline.
- Onto today’s map. The tithe map was first fitted to the georeferenced OS six-inch map of c.1900 (version 0.1). In version 0.2 the whole layer, parcels and old-map overlays together, was re-aligned to today’s ground with a correction fitted to seven control points on OpenStreetMap: St Dochdwy’s church, the mouth of the Cwm Cydfin stream at the Ely, the north tip of the Ely meander round plot 216, the Ely’s north-west bend and first bend, the curve of the Cwm Cydfin stream, and a field boundary on Penlan Road. Before, those points sat about 86 m off (the layer was shifted north-west, turned about 5° and drawn about 13% too small); after, the error is about 7 m (RMS). The plan was fitted to the tithe map field by field (about 13 m RMS).
- H3. Pick a resolution: 8 (the Bloculus resolution, about 0.74 km² a cell; the cell holding each parcel’s centre), or 10 to 15, from about 1.5 ha down to about 0.9 m² a cell. Resolution 15 is the finest the H3 grid has. From 10 up, the hexagons are worked out in your browser for the part of the map in view: a cell is drawn when its centre falls inside a parcel, in that parcel’s colour. Resolutions 14 and 15 draw once you zoom in close (a parcel at res 15 holds tens of thousands of cells), and at most about 20,000 cells are drawn at once.
Traffic light (v0.3.0). Family-associated land, as a working classification, not a legal finding. Green, Parcel A: plan parcels over 1841 tithe plots 209, 211, 219 and 220 (house and yard, orchard, wood strip, field), a working match not yet checked against a dated plan of Parcel A. Amber, Parcel B: plan parcels 5 and 6, over 1841 tithe plot 193, a match not checked. Amber, Leckwith Common and the playing fields: land in the City of Cardiff (Leckwith Common) Compulsory Purchase Order 1957, confirmed 1958; its extent is not yet located, so a pin marks today’s Leckwith Moors park as a guide. Amber, Parcel C: no boundary is held, so it is not drawn. Red: every other parcel on the estate plan.
Owner and occupier columns are the 1841 apportionment exactly as entered. Which plan parcel matches which tithe plot is our reading. With the re-alignment the traced parcels add up to about 140 acres, against 139a 3r 8p on the plan; before it they came to 105 acres, because the layer was drawn too small. The river course has moved a little since 1841, so the Ely itself can sit a few metres off the old banks.