# MEIの譜例と、注に置く校異

> MEI 5のブロックを5 mmの譜表で本文中に刻み、異読はapp・lem・rdgで符号化し、校異は小節と音符ごとに脚注に置きます。

- HTML版: https://postext.dev/ja/cookbook/musicology-mei-apparatus
- レシピ No. 165 · 囲みと注 · 難易度 2 (中級) · 出力: Canvas, PDF
- ジャンル: 論文・学術書
- 必要なもの postext ≥ 1.54.0, postext-pdf ≥ 1.54.0 · テスト環境 1.54.0, postext-pdf 1.54.0 ／テスト日 2026-10-22
- ページ: [1](https://postext.dev/cookbook/musicology-mei-apparatus/en/p01.webp?v=cd2d6301), [2](https://postext.dev/cookbook/musicology-mei-apparatus/en/p02.webp?v=cd2d6301), [3](https://postext.dev/cookbook/musicology-mei-apparatus/en/p03.webp?v=cd2d6301), [4](https://postext.dev/cookbook/musicology-mei-apparatus/en/p04.webp?v=cd2d6301), [5](https://postext.dev/cookbook/musicology-mei-apparatus/en/p05.webp?v=cd2d6301)
- PDF: https://postext.dev/cookbook/musicology-mei-apparatus/en/musicology-mei-apparatus.pdf?v=cd2d6301
- Sandboxで開く: https://postext.dev/ja/sandbox#recipe=musicology-mei-apparatus&lang=en (.postext: https://postext.dev/cookbook/musicology-mei-apparatus/en/musicology-mei-apparatus.postext)
- 最終更新: 2026-10-22
- 他の言語: [en](https://postext.dev/en/cookbook/musicology-mei-apparatus.md), [es](https://postext.dev/es/cookbook/musicology-mei-apparatus.md), [ca](https://postext.dev/ca/cookbook/musicology-mei-apparatus.md), [de](https://postext.dev/de/cookbook/musicology-mei-apparatus.md), [fr](https://postext.dev/fr/cookbook/musicology-mei-apparatus.md), [it](https://postext.dev/it/cookbook/musicology-mei-apparatus.md), [pt](https://postext.dev/pt/cookbook/musicology-mei-apparatus.md), [zh](https://postext.dev/zh/cookbook/musicology-mei-apparatus.md), [ar](https://postext.dev/ar/cookbook/musicology-mei-apparatus.md)

## かんたんな説明

中世音楽の研究書の一章です。13世紀イングランドの輪唱曲の短い部分を本文中に楽譜として印刷し、各ページの下の注で、古い版どうしの食い違いを小節ごとに記録します。

## できあがり

イングランドの好古家たちが中世音楽をどう読んだかを扱う研究書の第3章です。判型156 × 234 mmの5ページで、レディングの輪唱曲 *Sumer is icumen in* と、1776年から1889年にかけてこれを総譜にした編者たちを論じます。輪唱曲の3か所を、Leipzigの書体と5 mmの譜表で本文中に刻み、小節番号はW. S. Rockstroの総譜に合わせています。各段落はページの下の校異を引きます。「b. 40, n. 2 A ] G Hw, Bu」。注は校異らしく短く詰まり、楽譜は本文の行長いっぱいに収まります。どの異読もGroveの『音楽・音楽家事典』にRockstroが書いた項目によるもので、章の第2段落でそのことを明記しています。

**このレシピが答える問い:**

- 譜例に、資料ごとの異読を記した校異を脚注で付けるには？
- 脚注を付けるには？

## 手短な答え

````js
// script.js, 行 36–60
// In the Markdown each example is a ```mei fence. A variant is encoded where it stands,
// <app><lem>…</lem><rdg source="#Hw #Bu">…</rdg></app>: the staff shows the lemma, and
// the file keeps the reading for anyone who opens the encoding. The apparatus entry is a
// footnote cited from the paragraph that discusses the bar: `[^b40]: **b. 40, n. 2** A ] G`.
const scoreStyle = {
  staffSize: mm(5), // running-text examples: 4.5–5.5 mm
  musicFont: 'Leipzig', // lighter than Bravura, close to a 19th-century plate
  textFont: 'Crimson Pro', // the underlay in the book's own face
  barNumbers: 'system', // the apparatus is keyed by bar: number every system
  spacing: 0.95,
  systemGap: mm(4),
  marginTop: pt(4),
  marginBottom: pt(LEAD / 2),
  color: col('ink'),
  minSystemsAtBreak: 2, // never leave one system of an example alone at a page foot
};
const footnotes = {
  placement: 'column', // the foot of the page in one column
  numbering: 'chapter',
  fontSize: pt(8.5),
  lineHeight: pt(10.75),
  hangingIndent: em(1.2), // turnover lines align past the number
  spaceBetween: pt(2),
  separator: { width: 0.2, lineWidth: pt(0.5), color: col('rubric') },
};
````

## 材料

**学べること**

- [楽譜の記譜](https://postext.dev/ja/docs/music.md#本文中の楽譜): ```abc、```musicxml、```mei、```humdrumのフェンスにテキストで書いた楽譜です。Verovioが段の幅で浄書し、段や次のページへ続く段落（システム）に分けます。
- [脚注](https://postext.dev/ja/docs/document-format-notes-references.md#脚注): [^id]で参照する注です。参照した段の下端か章の後に置き、章ごと、または本全体の通し番号を振ります。

**ほかに使うもの**

- [楽譜スタイル](https://postext.dev/ja/docs/configuration-resources.md#楽譜スタイル)
- [デザインした章扉](https://postext.dev/ja/docs/configuration-headings.md#幅と詳細デザイン)
- [見出しの属性](https://postext.dev/ja/docs/document-format.md#見出しの属性)
- [柱とノンブル](https://postext.dev/ja/docs/configuration-headers-footers.md#柱とノンブル)
- [見開きの余白](https://postext.dev/ja/docs/configuration-page-layout.md#見開きの余白)
- [ページの役割ごとの柱](https://postext.dev/ja/docs/configuration-headers-footers.md#テキスト要素)
- [段落スタイル](https://postext.dev/ja/docs/configuration-styles.md#段落スタイル)
- [セマンティックカラーパレット](https://postext.dev/ja/docs/configuration-fonts-colors-viewers.md#カラーパレット)
- [用紙の色](https://postext.dev/ja/docs/configuration-page-layout.md#ページ)
- [ウィドウ、オーファン、ラント](https://postext.dev/ja/docs/configuration-page-flow.md#オーファンウィドウラント分割禁止の規則)
- [PDFの書き出し](https://postext.dev/ja/docs/configuration-pdf-output.md#pdfの生成)
- [コードリスト](https://postext.dev/ja/docs/configuration-styles.md#コードリスト)
- [段末そろえ](https://postext.dev/ja/docs/configuration-page-flow.md#段末そろえ)
- [PDFに埋め込むフォント](https://postext.dev/ja/docs/configuration-pdf-output.md#なぜフォントプロバイダーが必要か)

**設定の一覧**

- [`bodyText`](https://postext.dev/ja/docs/configuration-text.md#本文), [`colorPalette`](https://postext.dev/ja/docs/configuration-fonts-colors-viewers.md#カラーパレット), [`footer`](https://postext.dev/ja/docs/configuration-headers-footers.md#柱とノンブル), `footnotes`, [`header`](https://postext.dev/ja/docs/configuration-headers-footers.md#柱とノンブル), [`headings`](https://postext.dev/ja/docs/configuration-headings.md#見出し), [`layout`](https://postext.dev/ja/docs/configuration-page-layout.md#レイアウト), [`locale`](https://postext.dev/ja/docs/configuration-language.md#ハイフネーション), [`page`](https://postext.dev/ja/docs/configuration-page-layout.md#ページ), [`paragraphStyles`](https://postext.dev/ja/docs/configuration-styles.md#段落スタイル), [`scoreStyle`](https://postext.dev/ja/docs/configuration-resources.md#楽譜スタイル)

**API**

- [`buildDocumentWithFonts`](https://postext.dev/ja/docs/configuration-programmatic-usage.md#レイアウトの前にフォントを読み込む), [`decompressWoff2`](https://postext.dev/ja/docs/configuration-pdf-output.md#ブラウザー向けフォントプロバイダーfontsource--woff2), [`initMusicEngine`](https://postext.dev/ja/docs/music.md#本文中の楽譜), [`renderPageToCanvas`](https://postext.dev/ja/docs/configuration-programmatic-usage.md#ページをビットマップに描画する), [`renderToPdf`](https://postext.dev/ja/docs/configuration-pdf-output.md#pdfの生成)

**書体**

- Crimson Pro (OFL-1.1), Cormorant Garamond (OFL-1.1), Source Sans 3 (OFL-1.1)

## 作り方

### 1 · 譜例をMEIで書き、異読も書き込む

設定は上の[手短な答え](https://postext.dev/ja/cookbook/musicology-mei-apparatus.md#手短な答え)にあります。音楽はMarkdownの中に、譜例ごとに1つの ```` ```mei ```` ブロックで書きます。資料が食い違う箇所では、小節に `<app>` を置き、採った読みを `<lem>` に、もう一方を `<rdg source="#Hw #Bu">` に入れます。刻まれるのは `<lem>` なので、[譜例3.3](https://postext.dev/cookbook/musicology-mei-apparatus/en/p05.webp?v=cd2d6301)の第40小節にはAが印刷され、HawkinsとBurneyのGは符号化を開く人のためにファイルに残ります。各ブロックにはページの言語で `alt` を付けます。スクリーンリーダーとタグ付きPDFが楽譜について読み上げるのはこの文です。

### 2 · 校異を、読者に見える小節に結びつける

`barNumbers: 'system'` は各段の最初の小節に番号を付けます。各ブロックの `<measure n="37">` は、依拠した版でその部分が始まる番号から数え始めるので、譜例3.3は37から始まり、注の「b. 40」は読者が見つけられる小節を指します。校異の項目は普通の脚注で、その小節を論じる段落から引きます。採った読み、閉じ角括弧、異読、斜体の略号の順です。楽譜の中からは注を引けないので、合印はその読みを挙げる文に付けます。

### 3 · 本文に合う大きさで楽譜を組む

5 mmのLeipzigの譜表は116 mmの行長に、3/2拍子の小節を1段に5〜6小節入れて収まり、譜例3.3の11小節は2段になります。`textFont` は歌詞を本文の書体Crimson Proで組み、`minSystemsAtBreak: 2` は、譜例の1段だけをページの終わりに残して残りを次のページへ送ることを防ぎます。譜例の見出しは第3レベルの見出しなので、楽譜を伴わずにページの下に取り残されることはありません。

### 4 · 注のあるページは短く終わらせる

```js
// script.js, 行 64–78
const opener = {
  enabled: true,
  minHeight: mm(50), // every chapter's text starts on the same grid line
  slot: { elements: [
    { kind: 'text', id: 'kicker', content: '{attr.kicker}', ...label, fontSize: pt(8.5),
      letterSpacing: pt(1.8), color: col('rubric'), align: 'left',
      placement: at('container', 'top-left', 0, 8) },
    { kind: 'text', id: 'title', content: '{titleText}', fontFamily: 'Cormorant Garamond',
      italic: true, fontWeight: 500, fontSize: pt(29), lineHeight: 1.05, color: col('ink'),
      align: 'left', overflow: 'wrap', // design text ends in an ellipsis by default
      placement: { ...at('#kicker', 'below', 0, 3), size: { width: mm(100), height: 'auto' } } },
    { kind: 'rule', id: 'rule', direction: 'horizontal', thickness: pt(1), color: col('rubric'),
      placement: { ...at('#title', 'below', 0, 5), size: { width: mm(14) } } },
  ] },
};
```

章扉は本文をCormorantのイタリックの題の下、50 mmまで下げます。その先で、次の行が長い注を連れてくるページは数行早く終わります。`balancing: { maxLinesPerHeading: 1 }` は、段の均等化がその空きを次の節見出しの上へ移すのを防ぎます。そこに空きがあると、論の流れが切れたように見えるからです。

### 5 · 偶数ページに書名、奇数ページに章名

```js
// script.js, 行 82–99
const head = (id, content, parity, edge, x, extra = {}) => ({
  kind: 'text', id, content, parity, pages: 'body', // never on the opener
  ...label, fontSize: pt(7.5), letterSpacing: pt(1.3), color: col('muted'),
  placement: at('page', edge, x, 13), ...extra,
});
const folio = { color: col('rubric'), fontWeight: 700 };
const header = { elements: [
  head('verso-folio', '{pageNumber}', 'even', 'top-left', MARGIN.outer,
    { ...folio, align: 'left' }),
  head('verso-title', '{title}', 'even', 'top-left', MARGIN.outer + 8, { align: 'left' }),
  head('recto-title', '{chapterTitle}', 'odd', 'top-right', -(MARGIN.outer + 8),
    { align: 'right', overflow: 'ellipsis' }),
  head('recto-folio', '{pageNumber}', 'odd', 'top-right', -MARGIN.outer,
    { ...folio, align: 'right' }),
] };
// The opener carries a drop folio instead, centred under the text block.
const footer = { elements: [{ ...head('drop-folio', '{pageNumber}', 'all', 'bottom', 0,
  { ...folio, align: 'center', placement: at('page', 'bottom', 0, -11) }), pages: 'opener' }] };
```

ノンブルは朱色で外側に置き、偶数ページに書名、奇数ページに章名を入れます。`pages: 'body'` で章扉からは外し、章扉にはページ下の中央にノンブルを置きます。

## レシピの全体

レシピのフォルダーから合成した1つのファイルで、サンプルのテキストとレシピ集の共通キットを埋め込んであり、自分でページを組み立てます。動かすには、空のページの`<script type="module">`に入れるか、新しいCodePenのpenのJSパネルに貼り付けます（モジュールとして）。esm.shからpostextを読み込むので、インストールもビルドも要りません。

- レシピのフォルダー: https://github.com/drnachio/postext/tree/main/cookbook/musicology-mei-apparatus

### script.js

````js
// ═══ Postext Cookbook · Nº 165 · MEI music examples with a critical apparatus ═════
// https://postext.dev/en/cookbook/musicology-mei-apparatus
// Code: MIT · Text: original (CC BY 4.0) · Music: Sumer is icumen in, after Rockstro (PD)
// Fonts: Crimson Pro, Cormorant Garamond, Source Sans 3 (SIL OFL 1.1) · Needs postext ≥ 1.54.0
import {
  buildDocumentWithFonts, renderPageToCanvas, initMusicEngine,
} from 'https://esm.sh/postext';
import { renderToPdf, decompressWoff2 } from 'https://esm.sh/postext-pdf';

const LANG = 'en'; // @lang: the language of the sample document ('en' | 'es')
const RECIPE = 'musicology-mei-apparatus';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
// #region palette: a rubric red for kickers, labels and the notes' rule; ink on cream
const palette = {
  ink: '#211d1a', // text and notation: a warm near-black
  rubric: '#8c2f1f', // the one accent, the red of the manuscript's rubrics
  muted: '#6c645b', // running heads, colophon
  rule: '#cbbfae', // hairlines
  paper: '#fcfaf6',
};
// col(id): a colour linked to its palette entry, with the entry's hex beside the id.
const col = (id) => ({ hex: palette[id], model: 'hex', paletteId: id });
const colorPalette = [
  ...Object.entries(palette).map(([id, hex]) => ({ id, name: id, value: { hex, model: 'hex' } })),
  // The engine's defaults link to main-color: point it at the accent, never the default blue.
  { id: 'main-color', name: 'accent (defaults)', value: { hex: palette.rubric, model: 'hex' } },
];
// #endregion
const MARGIN = { top: 22, bottom: 22, inner: 19, outer: 21 }; // 156 × 234 mm, mirrored
const LEAD = 14.5; // body leading in pt: the baseline grid
const at = (to, edge, x = 0, y = 0) => ({ anchor: { to, edge }, offset: { x: mm(x), y: mm(y) } });
const label = { fontFamily: 'Source Sans 3', fontWeight: 600, textTransform: 'uppercase' };

// #region answer: MEI examples engraved in the text, their apparatus in footnotes
// In the Markdown each example is a ```mei fence. A variant is encoded where it stands,
// <app><lem>…</lem><rdg source="#Hw #Bu">…</rdg></app>: the staff shows the lemma, and
// the file keeps the reading for anyone who opens the encoding. The apparatus entry is a
// footnote cited from the paragraph that discusses the bar: `[^b40]: **b. 40, n. 2** A ] G`.
const scoreStyle = {
  staffSize: mm(5), // running-text examples: 4.5–5.5 mm
  musicFont: 'Leipzig', // lighter than Bravura, close to a 19th-century plate
  textFont: 'Crimson Pro', // the underlay in the book's own face
  barNumbers: 'system', // the apparatus is keyed by bar: number every system
  spacing: 0.95,
  systemGap: mm(4),
  marginTop: pt(4),
  marginBottom: pt(LEAD / 2),
  color: col('ink'),
  minSystemsAtBreak: 2, // never leave one system of an example alone at a page foot
};
const footnotes = {
  placement: 'column', // the foot of the page in one column
  numbering: 'chapter',
  fontSize: pt(8.5),
  lineHeight: pt(10.75),
  hangingIndent: em(1.2), // turnover lines align past the number
  spaceBetween: pt(2),
  separator: { width: 0.2, lineWidth: pt(0.5), color: col('rubric') },
};
// #endregion

// #region opener: kicker, a Cormorant italic title and a short red rule, sunk 50 mm
const opener = {
  enabled: true,
  minHeight: mm(50), // every chapter's text starts on the same grid line
  slot: { elements: [
    { kind: 'text', id: 'kicker', content: '{attr.kicker}', ...label, fontSize: pt(8.5),
      letterSpacing: pt(1.8), color: col('rubric'), align: 'left',
      placement: at('container', 'top-left', 0, 8) },
    { kind: 'text', id: 'title', content: '{titleText}', fontFamily: 'Cormorant Garamond',
      italic: true, fontWeight: 500, fontSize: pt(29), lineHeight: 1.05, color: col('ink'),
      align: 'left', overflow: 'wrap', // design text ends in an ellipsis by default
      placement: { ...at('#kicker', 'below', 0, 3), size: { width: mm(100), height: 'auto' } } },
    { kind: 'rule', id: 'rule', direction: 'horizontal', thickness: pt(1), color: col('rubric'),
      placement: { ...at('#title', 'below', 0, 5), size: { width: mm(14) } } },
  ] },
};
// #endregion

// #region running-heads: book title on the verso, chapter on the recto, folios outside
const head = (id, content, parity, edge, x, extra = {}) => ({
  kind: 'text', id, content, parity, pages: 'body', // never on the opener
  ...label, fontSize: pt(7.5), letterSpacing: pt(1.3), color: col('muted'),
  placement: at('page', edge, x, 13), ...extra,
});
const folio = { color: col('rubric'), fontWeight: 700 };
const header = { elements: [
  head('verso-folio', '{pageNumber}', 'even', 'top-left', MARGIN.outer,
    { ...folio, align: 'left' }),
  head('verso-title', '{title}', 'even', 'top-left', MARGIN.outer + 8, { align: 'left' }),
  head('recto-title', '{chapterTitle}', 'odd', 'top-right', -(MARGIN.outer + 8),
    { align: 'right', overflow: 'ellipsis' }),
  head('recto-folio', '{pageNumber}', 'odd', 'top-right', -MARGIN.outer,
    { ...folio, align: 'right' }),
] };
// The opener carries a drop folio instead, centred under the text block.
const footer = { elements: [{ ...head('drop-folio', '{pageNumber}', 'all', 'bottom', 0,
  { ...folio, align: 'center', placement: at('page', 'bottom', 0, -11) }), pages: 'opener' }] };
// #endregion

const config = {
  locale: t({ en: 'en-gb', es: 'es' }), // the language of the hyphenation patterns
  colorPalette,
  page: { sizePreset: 'custom', width: mm(156), height: mm(234), dpi: 150,
    backgroundColor: col('paper'),
    margins: { top: mm(MARGIN.top), bottom: mm(MARGIN.bottom), left: mm(MARGIN.inner),
      right: mm(MARGIN.outer), mirror: true } }, // left = inner
  layout: { layoutType: 'single' },
  bodyText: { fontFamily: 'Crimson Pro', fontSize: pt(11), lineHeight: pt(LEAD),
    color: col('ink'), boldColor: col('ink'), italicColor: col('ink'), referenceColor: col('ink'),
    textAlign: 'justify', firstLineIndent: mm(4.5), indentAfterHeading: false,
    hyphenation: { enabled: true }, optimalLineBreaking: true,
    avoidWidows: true, avoidOrphans: true, avoidRunts: true },
  headings: { fontFamily: 'Crimson Pro', color: col('ink'),
    // A page whose next line cannot take its footnote ends short: at most one extra grid
    // line goes above a heading, the rest stays at the foot, as in a book with notes.
    balancing: { maxLinesPerHeading: 1 },
    levels: [
    { level: 1, advancedDesign: opener, marginBottom: pt(0),
      breakBefore: { enabled: true, parity: 'odd' } },
    { level: 2, fontFamily: 'Cormorant Garamond', fontSize: pt(14), lineHeight: pt(LEAD),
      fontWeight: 600, italic: true, color: col('ink'), marginTop: pt(LEAD), marginBottom: pt(3) },
    // The example labels: a heading keeps itself with the score under it.
    { level: 3, ...label, fontSize: pt(7.5), lineHeight: pt(LEAD), letterSpacing: pt(1.1),
      color: col('rubric'), marginTop: pt(LEAD / 2), marginBottom: pt(0) },
  ] },
  paragraphStyles: [
    { id: 'colophon', ...label, textTransform: 'none', fontWeight: 400, fontSize: pt(7.5),
      lineHeight: pt(10), color: col('muted'), textAlign: 'left', firstLineIndent: pt(0),
      marginTop: pt(LEAD) },
  ],
  scoreStyle,
  footnotes,
  header,
  footer,
};

// ─── 2 · Content ────────────────────────────────────────────────────────────
const markdown = `---
title: "The Antiquaries’ Middle Ages"
---

# The Reading Rota and Its Editors {kicker="Chapter 3"}

No piece of medieval music was printed, scored and argued over by English antiquaries as often as the six-voice rota *Sumer is icumen in*. It survives on a single leaf, fol. 11v of the miscellany that Humfrey Wanley described for the Earl of Oxford around 1709 and that is now British Library, Harley MS 978. Wanley called it the oldest piece of its kind he had seen. Between Sir John Hawkins’s *General History* of 1776 and the article that William Smyth Rockstro wrote for George Grove’s *Dictionary of Music and Musicians*, the rota went through at least five scores, each claiming to correct the last.

This chapter follows that sequence of editions and tests it at three places where the editors disagreed. The music examples are new transcriptions, and their critical apparatus stands in the notes: each entry gives the bar and the note, the reading adopted, a closing bracket, and the readings of the other witnesses.

## The witnesses and this edition

Four witnesses are cited. **H** is the manuscript. **Hw** is the score in the first volume of Hawkins’s *General History of the Science and Practice of Music* (1776). **Bu** is the score in the second volume of Charles Burney’s *General History of Music* (1782). **Ro** is Rockstro’s solution of the canon, printed with the first part of his article in the third volume of Grove’s *Dictionary*.[^ro]

The examples follow Ro in pitch, clefs and note values, since Rockstro is the only editor of the period who explains every substitution he made. The manuscript, he writes, uses only a C clef, the *B rotundum*, square black notes with tails, one square note without a tail, and black lozenges. He renders a tailed note as a dotted semibreve when it is perfect and as a semibreve when it is imperfect, the untailed square note as a semibreve, and the lozenges as minims, under a signature of perfect time with the lesser prolation, “closely corresponding with the Signature 3-2 in modern Music”.[^values] The readings of H, Hw and Bu below are those that Rockstro reports. This chapter has not collated the two eighteenth-century prints afresh, and where Rockstro is silent, the apparatus is silent too.

## The first phrase and a corrected note

### Example 3.1 · Cantus I, bars 1–7, with the English and Latin texts

\`\`\`mei {alt="Sumer is icumen in, the first voice, bars 1 to 7, with the English words and the Latin text Perspice Christicola"}
<mei xmlns="http://www.music-encoding.org/ns/mei" meiversion="5.1">
<meiHead><fileDesc><titleStmt><title>Sumer is icumen in, Cantus I, bars 1–7</title></titleStmt><pubStmt/><sourceDesc><source xml:id="H"><bibl>BL Harley 978, f. 11v</bibl></source><source xml:id="Ro"><bibl>Rockstro, Grove iii</bibl></source></sourceDesc></fileDesc></meiHead>
<music><body><mdiv><score>
<scoreDef meter.count="3" meter.unit="2" keysig="1f"><staffGrp><staffDef n="1" lines="5" clef.shape="G" clef.line="2"/></staffGrp></scoreDef>
<section>
<measure n="1"><staff n="1"><layer n="1"><note pname="f" oct="5" dur="1"><verse n="1"><syl wordpos="i" con="d">Sum</syl></verse><verse n="2"><syl wordpos="i" con="d">Per</syl></verse></note><app><lem><note pname="e" oct="5" dur="2"><verse n="1"><syl wordpos="t">er</syl></verse><verse n="2"><syl wordpos="m" con="d">spi</syl></verse></note></lem><rdg source="#H"><note pname="f" oct="5" dur="2"><verse n="1"><syl wordpos="t">er</syl></verse><verse n="2"><syl wordpos="m" con="d">spi</syl></verse></note></rdg></app></layer></staff></measure>
<measure n="2"><staff n="1"><layer n="1"><note pname="d" oct="5" dur="1"><verse n="1"><syl>is</syl></verse><verse n="2"><syl wordpos="t">ce</syl></verse></note><note pname="e" oct="5" dur="2"><verse n="1"><syl wordpos="i" con="d">i</syl></verse><verse n="2"><syl wordpos="i" con="d">Chri</syl></verse></note></layer></staff></measure>
<measure n="3"><staff n="1"><layer n="1"><note pname="f" oct="5" dur="1"><verse n="1"><syl wordpos="m" con="d">cum</syl></verse><verse n="2"><syl wordpos="m" con="d">sti</syl></verse></note><note pname="f" oct="5" dur="2"><verse n="1"><syl wordpos="t">en</syl></verse><verse n="2"><syl wordpos="m" con="d">co</syl></verse></note></layer></staff></measure>
<measure n="4"><staff n="1"><layer n="1"><note pname="e" oct="5" dur="2" dots="1"><verse n="1"><syl>in,</syl></verse><verse n="2"><syl wordpos="t">la,</syl></verse></note><note pname="d" oct="5" dur="4"/><note pname="c" oct="5" dur="2"/></layer></staff></measure>
<measure n="5"><staff n="1"><layer n="1"><note pname="a" oct="4" dur="1"><verse n="1"><syl wordpos="i" con="d">Lhud</syl></verse><verse n="2"><syl>que</syl></verse></note><note pname="a" oct="4" dur="2"><verse n="1"><syl wordpos="t">e</syl></verse><verse n="2"><syl wordpos="i" con="d">dig</syl></verse></note></layer></staff></measure>
<measure n="6"><staff n="1"><layer n="1"><note pname="b" oct="4" dur="1"><verse n="1"><syl>sing</syl></verse><verse n="2"><syl wordpos="m" con="d">na</syl></verse></note><note pname="g" oct="4" dur="2"><verse n="1"><syl wordpos="i" con="d">cuc</syl></verse><verse n="2"><syl wordpos="m" con="d">ci</syl></verse></note></layer></staff></measure>
<measure n="7"><staff n="1"><layer n="1"><note pname="a" oct="4" dur="1" dots="1"><verse n="1"><syl wordpos="t">cu.</syl></verse><verse n="2"><syl wordpos="t">o.</syl></verse></note></layer></staff></measure>
</section></score></mdiv></body></music></mei>
\`\`\`

The opening is the best-documented phrase of the rota, because Rockstro returned to the leaf itself in the second part of his article and listed the erasures he could see. The scribe corrected his own work in the same ink, and the first correction falls on the second note.[^b1] Rockstro took the erasures as improvements made while the piece was being written down rather than as repairs of a faulty copy, and used them to support his view that the canon grew out of a popular tune that a trained musician adjusted until its phrases fitted against one another.

Two further decisions are visible in bars 2 and 4. The Latin text is printed in full where the manuscript abbreviates the name of Christ,[^b2] and the single tailed lozenge under the word *in* becomes a dotted minim and a crotchet.[^b4] The flat in the signature stands for the *B rotundum* of the manuscript, which Rockstro reads as a B flat throughout.[^bflat]

## The pes

### Example 3.2 · Pes, bars 1–8, as scored by Rockstro

\`\`\`mei {alt="Sumer is icumen in, the two lower voices of the pes, bars 1 to 8"}
<mei xmlns="http://www.music-encoding.org/ns/mei" meiversion="5.1">
<meiHead><fileDesc><titleStmt><title>Sumer is icumen in, the pes, bars 1–8</title></titleStmt><pubStmt/><sourceDesc><source xml:id="Ro"><bibl>Rockstro, Grove iii</bibl></source></sourceDesc></fileDesc></meiHead>
<music><body><mdiv><score>
<scoreDef meter.count="3" meter.unit="2" keysig="1f"><staffGrp symbol="bracket" bar.thru="false"><staffDef n="1" lines="5" clef.shape="F" clef.line="4"/><staffDef n="2" lines="5" clef.shape="F" clef.line="4"/></staffGrp></scoreDef>
<section>
<measure n="1"><staff n="1"><layer n="1"><note pname="f" oct="3" dur="1" dots="1"><verse n="1"><syl>Sing</syl></verse></note></layer></staff><staff n="2"><layer n="1"><note pname="c" oct="4" dur="1" dots="1"><verse n="1"><syl>Sing</syl></verse></note></layer></staff></measure>
<measure n="2"><staff n="1"><layer n="1"><note pname="g" oct="3" dur="1" dots="1"><verse n="1"><syl wordpos="i" con="d">cuc</syl></verse></note></layer></staff><staff n="2"><layer n="1"><note pname="b" oct="3" dur="1" dots="1"><verse n="1"><syl wordpos="i" con="d">cuc</syl></verse></note></layer></staff></measure>
<measure n="3"><staff n="1"><layer n="1"><note pname="f" oct="3" dur="1" dots="1"><verse n="1"><syl wordpos="t">cu</syl></verse></note></layer></staff><staff n="2"><layer n="1"><note pname="c" oct="4" dur="1" dots="1"><verse n="1"><syl wordpos="t">cu.</syl></verse></note></layer></staff></measure>
<measure n="4"><staff n="1"><layer n="1"><note pname="g" oct="3" dur="1"><verse n="1"><syl>nu.</syl></verse></note><note pname="a" oct="3" dur="2"/></layer></staff><staff n="2"><layer n="1"><mRest/></layer></staff></measure>
<measure n="5"><staff n="1"><layer n="1"><note pname="c" oct="4" dur="1" dots="1"><verse n="1"><syl>Sing</syl></verse></note></layer></staff><staff n="2"><layer n="1"><note pname="f" oct="3" dur="1" dots="1"><verse n="1"><syl>Sing</syl></verse></note></layer></staff></measure>
<measure n="6"><staff n="1"><layer n="1"><note pname="b" oct="3" dur="1" dots="1"><verse n="1"><syl wordpos="i" con="d">cuc</syl></verse></note></layer></staff><staff n="2"><layer n="1"><note pname="g" oct="3" dur="1" dots="1"><verse n="1"><syl wordpos="i" con="d">cuc</syl></verse></note></layer></staff></measure>
<measure n="7"><staff n="1"><layer n="1"><note pname="c" oct="4" dur="1" dots="1"><verse n="1"><syl wordpos="t">cu.</syl></verse></note></layer></staff><staff n="2"><layer n="1"><note pname="f" oct="3" dur="1" dots="1"><verse n="1"><syl wordpos="t">cu</syl></verse></note></layer></staff></measure>
<measure n="8"><staff n="1"><layer n="1"><mRest/></layer></staff><staff n="2"><layer n="1"><note pname="g" oct="3" dur="1"><verse n="1"><syl>nu.</syl></verse></note><note pname="a" oct="3" dur="2"/></layer></staff></measure>
</section></score></mdiv></body></music></mei>
\`\`\`

Below the four voices of the canon the manuscript writes two short parts to be sung as a ground, each to the words *Sing cuccu nu*. The Latin rubric opens *Hanc rotam cantare possunt quatuor socii*: four companions can sing the round, not counting those who hold the pes. Each new voice begins “at the first note after the cross”, which Ro marks over bar 5. The first pes is repeated *faciens pausacionem in fine*, the second *pausans in medio et non in fine*.[^rubric] Ro follows the rubric exactly: the first pes rests in bar 8, the second in bar 4, so that one of the two lower voices is always sounding.

The pes is also where the eighteenth-century scores went most visibly wrong. According to Rockstro, Hawkins misread both of its ligatures and printed the passage incorrectly at every repetition; Burney corrected the mistake.[^lig] Neither ligature can be shown in a modern score, and Example 3.2 resolves both into separate notes, as Ro does.

Rockstro’s own analysis of the part-writing begins from this score. The fourth, sixth, seventh, eighth and twenty-fourth bars, he observes, are in strict two-part counterpoint “of irreproachable purity”, while the passage from bar 9 to bar 10 gives consecutive fifths between the first and third voices of the canon, and bars 37 to 39 three consecutive fifths between the first cantus and the second voice of the pes.[^fifths] For Rockstro the mixture of styles was the strongest argument for a melody older than its harmony.

## The question of date

The dates proposed for the leaf say as much about the editors as about the manuscript. Hawkins placed it in the middle of the fifteenth century, arguing that its notation was the *cantus figuratus* he credited to John Dunstable, who, Hawkins wrote, died in 1455; Rockstro called the reasoning an anachronism “absolutely worthless”.[^hawkins] Burney thought the piece not much later than the thirteenth or fourteenth century. Joseph Ritson referred the manuscript to the middle of the thirteenth, and Thomas Busby, reprinting Burney’s score note for note in 1819, returned it to the fifteenth.

The decisive arguments came from palaeography. In 1855 William Chappell published a coloured facsimile in *Popular Music of the Olden Time* and later argued that the leaf was written at Reading Abbey by a monk named John of Fornsete around 1226. In April 1862 Sir Frederick Madden noted on a flyleaf of the volume that the whole was of the thirteenth century and that its earlier part had been written at Reading about 1240, a date the Palaeographical Society adopted for its facsimile of 1878. On the Continent, Johann Nikolaus Forkel (1788), August Wilhelm Ambros (1862 and 1868) and Edmond de Coussemaker (1865) all wrote on the rota without seeing the manuscript, a point Rockstro makes against each of them in turn.[^continent] A more recent study puts the copying between 1261 and 1264.[^wulstan]

## “Cuccu” in bar 40

### Example 3.3 · Cantus I, bars 37–47

\`\`\`mei {alt="Sumer is icumen in, the first voice, bars 37 to 47, from Cuccu, cuccu to ne swik thu nauer nu"}
<mei xmlns="http://www.music-encoding.org/ns/mei" meiversion="5.1">
<meiHead><fileDesc><titleStmt><title>Sumer is icumen in, Cantus I, bars 37–47</title></titleStmt><pubStmt/><sourceDesc><source xml:id="Hw"><bibl>Hawkins 1776</bibl></source><source xml:id="Bu"><bibl>Burney 1782</bibl></source><source xml:id="Ro"><bibl>Rockstro, Grove iii</bibl></source></sourceDesc></fileDesc></meiHead>
<music><body><mdiv><score>
<scoreDef meter.count="3" meter.unit="2" keysig="1f"><staffGrp><staffDef n="1" lines="5" clef.shape="G" clef.line="2"/></staffGrp></scoreDef>
<section>
<measure n="37"><staff n="1"><layer n="1"><note pname="c" oct="5" dur="1" dots="1"><verse n="1"><syl wordpos="i" con="d">Cuc</syl></verse></note></layer></staff></measure>
<measure n="38"><staff n="1"><layer n="1"><note pname="d" oct="5" dur="1" dots="1"><verse n="1"><syl wordpos="t">cu,</syl></verse></note></layer></staff></measure>
<measure n="39"><staff n="1"><layer n="1"><note pname="c" oct="5" dur="1" dots="1"><verse n="1"><syl wordpos="i" con="d">cuc</syl></verse></note></layer></staff></measure>
<measure n="40"><staff n="1"><layer n="1"><note pname="b" oct="4" dur="1"><verse n="1"><syl wordpos="t">cu.</syl></verse></note><app><lem><note pname="a" oct="4" dur="2"/></lem><rdg source="#Hw #Bu"><note pname="g" oct="4" dur="2"/></rdg></app></layer></staff></measure>
<measure n="41"><staff n="1"><layer n="1"><note pname="f" oct="4" dur="1"><verse n="1"><syl>Wel</syl></verse></note><note pname="a" oct="4" dur="2"><verse n="1"><syl wordpos="i" con="d">sing</syl></verse></note></layer></staff></measure>
<measure n="42"><staff n="1"><layer n="1"><note pname="b" oct="4" dur="1"><verse n="1"><syl wordpos="t">es</syl></verse></note><note pname="g" oct="4" dur="2"><verse n="1"><syl>thu</syl></verse></note></layer></staff></measure>
<measure n="43"><staff n="1"><layer n="1"><note pname="a" oct="4" dur="1" dots="1"><verse n="1"><syl wordpos="i" con="d">cuc</syl></verse></note></layer></staff></measure>
<measure n="44"><staff n="1"><layer n="1"><note pname="b" oct="4" dur="1"><verse n="1"><syl wordpos="t">cu,</syl></verse></note><note pname="c" oct="5" dur="2"><verse n="1"><syl>ne</syl></verse></note></layer></staff></measure>
<measure n="45"><staff n="1"><layer n="1"><note pname="a" oct="4" dur="1"><verse n="1"><syl>swik</syl></verse></note><note pname="c" oct="5" dur="2"><verse n="1"><syl>thu</syl></verse></note></layer></staff></measure>
<measure n="46"><staff n="1"><layer n="1"><note pname="g" oct="4" dur="1"><verse n="1"><syl wordpos="i" con="d">nau</syl></verse></note><note pname="e" oct="4" dur="2"><verse n="1"><syl wordpos="t">er</syl></verse></note></layer></staff></measure>
<measure n="47"><staff n="1"><layer n="1"><note pname="f" oct="4" dur="1" dots="1"><verse n="1"><syl>nu.</syl></verse></note></layer></staff></measure>
</section></score></mdiv></body></music></mei>
\`\`\`

The last passage of the tune shows how an error could travel. Hawkins and Burney, Rockstro reports, both print a G where the manuscript has an A in bar 40, on the second syllable of *cuccu*, and they do so each time the phrase returns in a new voice.[^b40] Against Hawkins’s faulty pes the G passes; against Burney’s corrected pes it makes what Rockstro calls “a horrible discord”. The variant is encoded in the source of Example 3.3 as a reading of Hw and Bu, while the engraved staff shows the lemma.

Both historians also fitted the words to the notes differently from the manuscript from bar 41 onwards, at *Wel singes thu cuccu, ne swik thu nauer nu*.[^b41] Rockstro gives no details of their underlay, and the example therefore records only the fact. The one modern copy Rockstro knew went further and left out the pes, reducing the rota to four parts.

:::paragraphs{style="colophon"}
Set in Crimson Pro, Cormorant Garamond and Source Sans 3 (SIL OFL); music in Leipzig, engraved by Verovio · Text: original, CC BY 4.0 · Music: *Sumer is icumen in* (13th century), after W. S. Rockstro’s score in Grove’s *Dictionary of Music and Musicians*, iii, 766–767 (public domain)
:::

[^ro]: W. S. Rockstro, “Sumer is icumen in”, in G. Grove (ed.), *A Dictionary of Music and Musicians*, iii, 765–768, continued in iv, 1–3 (London: Macmillan, 1900 printing). The score, iii, 766–767, is cited from the Wikisource transcription of that printing.

[^values]: Ro, iii, 765. The tailed lozenge on the first note of *in* is the one exception (see the note on bar 4).

[^b1]: **b. 1, n. 2** E ] F *H* before correction (“The second note on Stave 1 was originally an F”, Ro, iv, 1). The reading before correction is encoded as a variant in Example 3.1.

[^b2]: **b. 2, n. 2 – b. 4, n. 1** *Chri-sti-co-la* ] abbreviated with the Greek letters *chi* and *rho* *H*, Ro. Expanded as Rockstro glosses it, *Christicola* (iii, 765).

[^b4]: **b. 4, nn. 1–2** dotted minim, crotchet ] one lozenge with a tail *H*, the only tailed lozenge in the manuscript, which Rockstro could “scarcely conceive to be accidental” (iii, 765).

[^bflat]: **bb. 1–7, signature** B flat ] *B rotundum* *H*. The flat is printed in the signature, as in Ro.

[^rubric]: The rubric is quoted from the transcription and translation in the Wikipedia article “Sumer is icumen in”, which also gives the folio. Rockstro scores the canon “in exact accordance with the Latin directions” (iii, 765) but does not print them.

[^lig]: **Pes, bb. 1–8** both ligatures misread at every statement *Hw*; corrected *Bu* (Ro, iii, 765). Rockstro does not say how Hawkins read them, so no variant is encoded.

[^fifths]: Ro, iv, 2. The bar numbers refer to Rockstro’s score and to the examples of this chapter.

[^hawkins]: Ro, iii, 765. Rockstro dates Hawkins’s first volume 1770; the *General History* appeared in 1776.

[^continent]: Ro, iii, 768, and iv, 1, citing Forkel, *Allgemeine Geschichte der Musik*, ii, 490–500; Ambros, *Geschichte der Musik*, ii, 473–475; Coussemaker, *L’Art harmonique*, 144.

[^wulstan]: D. Wulstan, “‘Sumer is icumen in’: A Perpetual Puzzle-Canon?”, *Plainsong and Medieval Music* 9 (2000), 1–17, at 8. Wulstan proposes W. de Wycombe as the scribe.

[^b40]: **b. 40, n. 2** A ] G *Hw*, *Bu* (and Busby 1819, after *Bu*), at every entry of the phrase (Ro, iii, 765). Encoded as a variant in Example 3.3.

[^b41]: **bb. 41–47, underlay** as *H* ] text placed otherwise under the notes *Hw*, *Bu* (Ro, iii, 765).
`; // content.<lang>.md, inlined by the Cookbook

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/** The files beyond latin `text` needs that `meta`'s family ships. */
function kitSubsetsFor(text, meta) {
  return [[/[Ā-˿ᴀ-ᶿḀ-ỿ†ℓⱠ-Ɀ꜠-ꟿ]/u, 'latin-ext'], [/[Ͱ-Ͽ]/u, 'greek']]
    .filter(([re, x]) => re.test(text) && meta?.subsets?.includes(x)).map(([, x]) => x);
}

/** Fontsource's id for a family: 'Source Serif 4' → 'source-serif-4'. */
function fontsourceId(family) { return family.toLowerCase().replace(/\s+/g, '-'); }

/** A package's folder at the one version @5 names now (#766). */
function fontsourceAt(id, u = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@`) {
  return (fontsourceAt.c ??= {})[id] ??= fetch(u + '5/package.json').then((r) => r.json())
    .then((p) => p.version || 5, () => 5).then((v) => `${u}${v}/`);
}

/** The family's Fontsource metadata (weights, styles, subsets), or null. */
function fontsourceMeta(family) {
  fontsourceMeta.cache ??= new Map();
  const id = fontsourceId(family);
  if (!fontsourceMeta.cache.has(id)) {
    fontsourceMeta.cache.set(id, fetch(`https://api.fontsource.org/v1/fonts/${id}`)
      .then((res) => (res.ok ? res.json() : null), () => null));
  }
  return fontsourceMeta.cache.get(id);
}

// ─── Kit · viewer v2 ── the same in every recipe · postext.dev/cookbook
/** The pages as spreads on a dark desk, page 1 alone, then verso | recto,
 *  each painted when it scrolls near. Other options go to renderPageToCanvas. */
function showPages(docs, { title, width = 460, ...render } = {}) {
  const root = viewer(title);
  const pages = [docs].flat().flatMap((doc) =>
    doc.pages.map((page) => ({ doc, page, n: (doc.pageIndexOffset ?? 0) + page.index })));
  const spreads = [];
  let verso = null;
  for (const p of pages) {
    if (p.n % 2 === 1) { if (verso) spreads.push([verso, null]); verso = p; }
    else { spreads.push([verso, p]); verso = null; }
  }
  if (verso) spreads.push([verso, null]);
  const density = Math.min(window.devicePixelRatio || 1, 2);
  showPages.painter?.disconnect();
  const painter = new IntersectionObserver((entries) => {
    for (const { isIntersecting, target } of entries) {
      if (!isIntersecting) continue;
      painter.unobserve(target);
      const { doc, page } = target.postext;
      renderPageToCanvas(page, doc, target, { ...render, scale: (width * density) / page.width });
    }
  }, { rootMargin: '800px' });
  showPages.painter = painter;
  root.replaceChildren(...spreads.map((pair) => {
    const spread = document.createElement('div');
    spread.className = 'pt-spread';
    for (const p of pair) {
      const figure = document.createElement('figure');
      if (p) {
        const label = p.page.pageLabel || String(p.n + 1);
        const canvas = document.createElement('canvas');
        canvas.postext = p;
        canvas.style.aspectRatio = `${p.page.width} / ${p.page.height}`;
        canvas.setAttribute('role', 'img');
        canvas.setAttribute('aria-label', `Page ${label}`);
        const folio = document.createElement('figcaption');
        folio.textContent = label;
        figure.append(canvas, folio);
        painter.observe(canvas);
      } else figure.className = 'pt-blank';
      spread.append(figure);
    }
    return spread;
  }));
  kitStatus(`${pages.length} ${pages.length === 1 ? 'page' : 'pages'}`);
  document.documentElement.dataset.postext = 'ready';
  return pages.length;
}

/** The desk, the bar and the error reporting, created once. */
function viewer(title) {
  if (!document.getElementById('pt-kit')) {
    document.head.insertAdjacentHTML('beforeend', `<style id="pt-kit">
      :root { color-scheme: dark; }
      body { margin: 0; background: #0e1014; color: #b9bcc4; font: 13px/1.45 system-ui, sans-serif; }
      #pt-bar { position: sticky; top: 0; z-index: 1; display: flex; flex-wrap: wrap; align-items: center;
        gap: 6px 16px; padding: 10px 16px; background: rgb(14 16 20 / .92); backdrop-filter: blur(6px);
        border-bottom: 1px solid #23262d; }
      #pt-bar strong { color: #f4f1ea; font-weight: 600; }
      #pt-actions { display: flex; gap: 12px; margin-left: auto; }
      #pt-actions a, #pt-actions button { color: #d8a21a; font: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
      #pages { display: grid; justify-items: center; gap: 48px; padding: 32px 16px 72px; }
      .pt-spread { display: flex; }
      .pt-spread figure { margin: 0; width: min(460px, 44vw); }
      .pt-spread canvas { display: block; width: 100%; background: #fff;
        box-shadow: 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figure:first-child canvas { box-shadow: inset -14px 0 14px -14px rgb(0 0 0 / .18), 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figcaption { margin-top: 10px; text-align: center; font: 600 10px/1 system-ui, sans-serif;
        letter-spacing: .18em; text-transform: uppercase; color: #6c7079; }
      .pt-blank { visibility: hidden; }
      @media (max-width: 760px) {
        .pt-spread { flex-direction: column; gap: 32px; }
        .pt-spread figure { width: min(460px, 92vw); }
        .pt-blank { display: none; }
      }
    </style>`);
    document.body.insertAdjacentHTML('afterbegin',
      '<header id="pt-bar"><strong id="pt-title"></strong><span id="pt-status" role="status"></span><span id="pt-actions"></span></header>');
    document.getElementById('pt-title').textContent = document.title || 'Postext';
    addEventListener('error', (event) => kitFail(event.error ?? event.message));
    addEventListener('unhandledrejection', (event) => kitFail(event.reason));
  }
  if (title) document.getElementById('pt-title').textContent = title;
  return document.getElementById('pages')
    ?? document.body.appendChild(Object.assign(document.createElement('main'), { id: 'pages' }));
}

function kitStatus(text) {
  viewer();
  document.getElementById('pt-status').textContent = text;
}

function kitFail(error) {
  document.documentElement.dataset.postext = 'error';
  kitStatus(`Error: ${error?.message ?? error}`);
}

// ─── Kit · pdf v3 ── the same in every recipe that exports a PDF
/** The Fontsource files the screen used, as TrueType, with their range and
 *  place: the nearest weight the family ships, upright with no italic;
 *  latin, then what its letters need (kitSubsetsFor). */
async function fontsourceProvider(family, weight, style, request) {
  const id = fontsourceId(family);
  const meta = await fontsourceMeta(family);
  const weights = meta?.weights?.length ? meta.weights : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const s = style === 'italic' && meta && !meta.styles.includes('italic') ? 'normal' : style;
  const text = String.fromCodePoint(...(request?.codePoints ?? []));
  const files = await Promise.all(['latin', ...kitSubsetsFor(text, meta)].map(async (subset, order) => {
    const res = await fetch(`${await fontsourceAt(id)}files/${id}-${subset}-${w}-${s}.woff2`);
    if (!res.ok) throw new Error(`Fontsource has no ${family} ${w} ${s} ${subset}`);
    return Object.assign(await decompressWoff2(new Uint8Array(await res.arrayBuffer())),
      { unicodeRange: kitRanges()[subset], order });
  }));
  return files.length === 1 ? files[0] : files;
}

/** A "Build the PDF" button; then "Open the PDF" (a new tab: CodePen's frame
 *  shows no PDFs) and a download link. */
function offerPdf(makePdf, filename) {
  viewer();
  const button = Object.assign(document.createElement('button'), { type: 'button', textContent: 'Build the PDF' });
  button.dataset.postextPdf = filename;
  button.addEventListener('click', async () => {
    button.disabled = true;
    button.textContent = 'Building the PDF…';
    try {
      const bytes = await makePdf();
      const url = URL.createObjectURL(new Blob([bytes], { type: 'application/pdf' }));
      const size = `${Math.max(1, Math.round(bytes.length / 1024))} KB`;
      button.replaceWith(
        Object.assign(document.createElement('a'), { href: url, target: '_blank', rel: 'noopener', textContent: 'Open the PDF ↗' }),
        Object.assign(document.createElement('a'), { href: url, download: filename, textContent: `Download ${filename} · ${size}` }));
    } catch (error) {
      button.disabled = false;
      button.textContent = 'Build the PDF';
      kitFail(error);
    }
  });
  document.getElementById('pt-actions').append(button);
}

// ─── /Kit ───────────────────────────────────────────────────────────────────────
````

## アレンジ

### すべての小節に番号を付ける

1段に校異の項目が多いときは、小節ごとに番号があるほうが追いやすくなります。

```diff
-  barNumbers: 'system', // the apparatus is keyed by bar: number every system
+  barNumbers: 'every',
```

### 譜例をBravuraで刻む

Bravuraの太めの符頭は、銅版彫刻風の社内様式によく合います。

```diff
-  musicFont: 'Leipzig', // lighter than Bravura, close to a 19th-century plate
+  musicFont: 'Bravura',
```

## よくあるつまずき

- MEI 5では調号を `scoreDef` か `staffDef` の `keysig="1f"` で書きます。MEI 4の属性 `key.sig` は知らせもなく無視され、フラットが消えます。
- どの `staffDef` にも `lines="5"` を付けます。これがないと、音符と音部記号は譜線のないところに刻まれます。
- 刻まれるのは `<app>` の `<lem>` で、`<rdg>` ではありません。ページ上で読者に見せたい異読は、校異の注か、もう1つの譜例に置きます。

## クレジット

- レシピ: Ignacio Ferro ([@drnachio](https://github.com/drnachio))
- テキスト: The chapter text and the apparatus notes, in English and Spanish: Ignacio Ferro, CC-BY-4.0
- テキスト: Sumer is icumen in (13th century), the music examples transcribed from W. S. Rockstro's score and the readings his article reports, in A Dictionary of Music and Musicians, ed. George Grove, vol. 3, pp. 765–768, and vol. 4, pp. 1–3 (Macmillan, 1900 printing), as transcribed on Wikisource: Anonymous; William Smyth Rockstro ([出典](https://en.wikisource.org/wiki/A_Dictionary_of_Music_and_Musicians/Sumer_is_icumen_in)), パブリックドメイン
- テキスト: The Latin rubric of Harley MS 978, f. 11v, and the folio, as quoted in the Wikipedia article (fact check): Wikipedia contributors ([出典](https://en.wikipedia.org/wiki/Sumer_is_icumen_in)), CC-BY-SA-4.0
- 書体: Crimson Pro (OFL-1.1), Cormorant Garamond (OFL-1.1), Source Sans 3 (OFL-1.1)
- コード: MIT · サンプルの内容: CC-BY-4.0

## 関連レシピ

- [No. 071 · 引用した段の地に置く脚注](https://postext.dev/ja/cookbook/novel-footnotes-column-foot.md): Markdownの[^id]の合印が、引用した段の地に置く番号付きの脚注になります。1段組み、章末注、通し番号への切り替えも付けています。 · 難易度 2 (中級) · 小説・戯曲・文芸
- [No. 044 · 校訂版：行番号と行に対応する注](https://postext.dev/ja/cookbook/critical-edition-line-numbers.md): 1645年版の本文によるミルトンの『Lycidas』。lineNumbersが詩の行を数えて5行ごとの番号をサイド段に印字し、各注はチップで組んだ行番号から始まります。 · 難易度 3 (上級) · 詩歌
- [No. 163 · ABCで譜例を書く和声の教科書](https://postext.dev/ja/cookbook/harmony-textbook-abc-examples.md): 終止を扱う和声の教科書の1章です。譜例はMarkdownに書いたABCのブロックで、段の幅に合わせて浄書され、そのうち1つは2ページにわたって続きます。 · 難易度 2 (中級) · 教科書