---
license: mit
task_categories:
  - text-generation
  - question-answering
language:
  - en
tags:
  - pdf2dataset
  - ocr
  - chunked
size_categories:
  - 1K<n<10K
---

# TheyCameBeforeColumbus

Dataset created with [PDF2Dataset](https://github.com/svngoku/PDF2Dataset) -- OCR + structure-aware chunking pipeline.

## Dataset Summary

| Metric | Value |
|---|---|
| Total chunks | 1092 |
| Avg chars/chunk | 583 |
| Avg images/chunk | 0.08 |
| Source files | 1 |
| Duplicates removed | 1 |
| Quality filtered | 43 |

## Schema

| Column | Type | Description |
|---|---|---|
| `chunk_id` | `string` | Unique identifier: `filename_chunk_N` |
| `text` | `string` | Raw markdown chunk with image refs |
| `text_clean` | `string` | Cleaned text without markdown formatting |
| `chapter` | `string` | H1 header active at chunk position |
| `section` | `string` | H2 header active at chunk position |
| `subsection` | `string` | H3+ header active at chunk position |
| `images` | `list[Image]` | Rendered images extracted from chunk (viewable in Dataset Viewer) |
| `image_refs` | `list[string]` | Image reference IDs in chunk text |
| `num_images` | `int` | Number of images in chunk |
| `has_images` | `bool` | Whether chunk contains images |
| `source_filename` | `string` | Original source file name |
| `start_index` | `int` | Character offset in source document |
| `char_count` | `int` | Character count of chunk text |

## Source Files

| File | Chunks |
|---|---|
| `They Came Before Columbus The African Presence in Ancient America by Ivan Van Sertima.pdf` | 1092 |

## Document Structure

Chapters found in the source documents:

- ABOUT THE AUTHOR
- ACKNOWLEDGMENTS
- AFRICAN-EGYPTIAN PRESENCES IN ANCIENT AMERICA
- AFRICANS ACROSS THE SEA
- AMONG THE QUETZALCOATLS
- BLACK AFRICA AND EGYPT
- CONTENTS
- INDEX
- IVAN VAN SERTIMA
- MANDINGO TRADERS IN MEDIEVAL MEXICO
- PHOTO CREDITS
- PLANTS AND TRANSPLANTS
- POSTSCRIPT ON OTHER FINDS
- SMOKING, TOBACCO AND PIPES IN AFRICA AND AMERICA
- THE BLACK KINGS OF THE TWENTY-FIFTH DYNASTY
- THE MARINER PRINCE OF MALI
- THE MYSTERY OF MU-LAN-P'I
- THE SECRET ROUTE FROM GUINEA
- THE VISIBLE WITNESSES
- THEY CAME BEFORE COLUMBUS

## Pipeline

This dataset was processed through the PDF2Dataset pipeline:

1. **OCR** -- Mistral OCR extracts text and images from PDF/image files
2. **Chunking** -- Structure-aware recursive splitting preserves document hierarchy
3. **Validation** -- Schema validation ensures every chunk has required fields
4. **Deduplication** -- Content-hash based dedup removes identical chunks
5. **Quality Filtering** -- Removes empty, too-short, or malformed chunks