| --- |
| language: |
| - en |
| license: cc-by-nc-4.0 |
| task_categories: |
| - image-to-text |
| - image-classification |
| pretty_name: 'London''s Pulse: MOH Reports (page images + OCR text)' |
| tags: |
| - archives |
| - glam |
| - historical |
| - iiif |
| - lam |
| - libraries |
| - medical-officer-of-health |
| - ocr |
| - public-health |
| - table-extraction |
| - tables |
| - wellcome-collection |
| dataset_info: |
| config_name: tables |
| features: |
| - name: image |
| dtype: image |
| - name: page_type |
| dtype: string |
| - name: table_ground_truth |
| dtype: string |
| - name: n_tables_on_page |
| dtype: int32 |
| - name: b_number |
| dtype: string |
| - name: page_index |
| dtype: int32 |
| - name: printed_page |
| dtype: int32 |
| - name: source_collection |
| dtype: string |
| - name: label_source |
| dtype: string |
| - name: split |
| dtype: string |
| - name: signals |
| dtype: string |
| splits: |
| - name: train |
| num_bytes: 448527779 |
| num_examples: 2520 |
| - name: validation |
| num_bytes: 52884161 |
| num_examples: 302 |
| - name: test |
| num_bytes: 56707410 |
| num_examples: 327 |
| download_size: 554397290 |
| dataset_size: 558119350 |
| configs: |
| - config_name: default |
| data_files: |
| - split: train |
| path: data/train-* |
| - config_name: tables |
| data_files: |
| - split: train |
| path: tables/train-* |
| - split: validation |
| path: tables/validation-* |
| - split: test |
| path: tables/test-* |
| --- |
| # London's Pulse: Medical Officer of Health reports (page images + OCR text) |
|
|
| Page-level scans of the Wellcome Collection [**London's Pulse**](https://wellcomelibrary.org/moh/) |
| Medical Officer of Health (MOH) reports (1848–1972), paired with OCR text, per-report |
| licence, and full provenance. Built for **OCR / VLM / document-understanding** work on real |
| historical public-health records — dense statistical tables, mixed layouts, century-old print. |
|
|
| ## Configs |
|
|
| | config | rows | what | |
| |---|---|---| |
| | `default` | 391,964 pages / 4,886 reports | every **page image** + its report's OCR text + licence | |
| | `tables` | 3,149 pages / 288 reports | selected page images paired with 3,980 machine-extracted tables; silver labels for page-type training and exploratory table-extraction evaluation | |
|
|
| ```python |
| from datasets import load_dataset |
| |
| # full corpus (stream — it's ~110 GB) |
| ds = load_dataset("biglam/londons-pulse-moh", split="train", streaming=True) |
| |
| # tables subset (small; image + silver table targets) |
| tab = load_dataset("biglam/londons-pulse-moh", "tables", split="test") |
| ``` |
|
|
| ## `default` config — columns |
|
|
| | column | type | description | |
| |---|---|---| |
| | `image` | `Image` | the page scan (full native resolution) | |
| | `b_number` | `string` | Wellcome report id (join key) | |
| | `page_index` | `int32` | 1-based page (scan) number within the report | |
| | `n_pages` | `int32` | total pages in the report | |
| | `report_text` | `string` | OCR text of the **whole report** (see caveat) | |
| | `license` | `string` | normalised image licence (all `cc-by-nc` here) | |
| | `table_ground_truth` | `string` | reserved (empty in `default`; populated in the `tables` config) | |
| | `signals` | `string` | JSON provenance (`manifest_url`, `image_service_id`, size/format, `license_raw`, multi-volume linkage) | |
|
|
| > [!IMPORTANT] |
| > **`report_text` is report-level, not page-aligned** — the source OCR is a flat per-report |
| > dump with no reliable page boundaries, so the same full-report text repeats across every |
| > page of that report. Group/dedupe by `b_number`. |
| |
| ## `tables` config — columns |
| |
| One row per scan with at least one matched table from Wellcome's machine-extracted |
| export. The attached tables are a **selected subset**, not an exhaustive annotation of |
| every table visible on the page. The CSV content remains uncorrected silver data. |
| Use for `table` page-type training or exploratory OCR/VLM evaluation with that limitation. |
| |
| | column | type | description | |
| |---|---|---| |
| | `image` | `Image` | the page scan | |
| | `page_type` | `string` | `"table"` | |
| | `table_ground_truth` | `string` | JSON list of `{table_id, csv}` — the extracted table(s) on that page | |
| | `n_tables_on_page` | `int32` | number of attached export tables; may be fewer than the tables visible on the page | |
| | `b_number`, `page_index`, `printed_page` | | report id, 1-based scan index, original numeric printed-page value (nullable when regrouped values differ); exact export labels are in `signals.export_page_labels` | |
| | `source_collection`, `label_source`, `split`, `signals` | | provenance (`label_source="table-export"`) | |
| |
| The original selection spans all 12 decades. Train/validation/test assignments remain |
| grouped by report, with no report shared across splits. After the September 2026 alignment |
| repair there are 2,520 / 302 / 327 rows respectively. Page counts increased because tables |
| previously conflated by repeated printed-page numbers now occupy separate scans. |
| |
| Alignment uses each table's content against **every page's ALTO in its report**; |
| numeric canvas labels alone do not decide the match. The automated rule requires |
| IDF-weighted token containment ≥0.70, a margin ≥0.10 over the next-best scan, and at least |
| eight distinct content tokens. Two low-margin matches were retained after explicitly |
| recorded agent visual checks. These scores measure agreement with source OCR, not the |
| probability of a correct annotation. Limited image checks supplement the automated pass; |
| the entire dataset has not been manually verified. |
| |
| The [alignment audit](audits/table-alignment-2026-09-09/README.md) accounts for all 4,086 |
| original table items: 3,529 retained on their original scan, 451 moved, and 106 unresolved. |
| Unresolved items are excluded from the image/table config and preserved with their original |
| CSV content in [unresolved.jsonl](audits/table-alignment-2026-09-09/unresolved.jsonl). |
| Table IDs, CSV strings and original report split assignments are conserved across the |
| config and that side artifact. The `default` corpus is unchanged. |
| |
| > [!NOTE] |
| > **Target quality — silver, not gold.** These tables were extracted by OCR/table recognition, |
| > not hand-transcribed. Known errors include incorrect digits, lost fractions, noisy captions |
| > and labels, flattened headers, shifted or missing cells, and inconsistent nil markers. |
| > Correcting the scan association does **not** correct those errors. Neither exact numeric |
| > scoring nor fuzzy text matching by itself accounts for this noise. Use an independently |
| > reviewed reference set for headline evaluation results. The original CSV strings, including |
| > any literal escaped line endings, are preserved; the repair script interprets those escapes |
| > only when parsing content for alignment. |
| |
| ## Provenance & reproducibility |
| |
| - **Images**: Wellcome [IIIF Presentation v2 API](https://iiif.wellcomecollection.org/), |
| keyed on each report's b-number. `default` uses native resolution; `tables` retains the |
| existing approximate 800/1,000-pixel width convention, including for replacement scans. |
| Actual dimensions (including IIIF rounding differences) are recorded in `signals.image_size`. |
| - **Text** (`default`): the bulk `Fulltext.zip` corpus from |
| [wellcomelibrary.org/moh](https://wellcomelibrary.org/moh/), joined on b-number. |
| - **Tables** (`tables`): Wellcome's `All_Report_Tables` export (~275k machine-extracted |
| tables). The original numeric-label resolver conflated duplicate and irregular printed |
| page labels. The [repair script](scripts/repair_table_alignment.py) performs report-wide |
| ALTO content matching and preserves the original export payloads. |
| - `signals` records the manifest and image service for each page. In `tables` it also |
| records the canvas label, export-page labels, image dimensions, source dataset revision |
| and alignment audit location. Per-table decisions and source checksums are in the audit. |
|
|
| ## Licence |
|
|
| Page **images** are **CC-BY-NC 4.0** (per Wellcome's IIIF manifests; per-row `license` + |
| `signals.license_raw`). The OCR **text** corpus is CC-BY 4.0; the extracted-tables export is |
| CC-BY 4.0. Reports whose image licence was not open were excluded. **Reuse is |
| non-commercial**, with attribution to **Wellcome Collection**. |
|
|
| | licence | pages (`default`) | |
| |---|---| |
| | cc-by-nc | 391,964 | |
|
|
| ## Source & attribution |
|
|
| Wellcome Collection, *London's Pulse: Medical Officer of Health reports 1848–1972*. |
| Images: `iiif.wellcomecollection.org` · Text/tables: `wellcomelibrary.org/moh`. |
|
|
| ## Intended uses |
|
|
| Historical OCR/VLM evaluation, document layout analysis, page-type classification, and |
| structured extraction from century-old public-health tables (disease incidence, mortality). |
| The `tables` config provides candidate material for image→table extraction evaluation; |
| reliable headline results require independently reviewed references. |
|
|
