How a Coal Fire Gave Wine Its First Strong Bottle — and Why Kenelm Digby Got the Credit

For most of wine’s history, the bottle was not where wine lived. Wine lived in the cask, and it travelled in the cask, and it was drawn from the cask into a jug at the last possible moment before it reached the glass. Glass vessels existed, and some were very beautiful, but they were for serving, not for keeping. They were thin, pale, and fragile, and a wine sealed inside one for any length of time was a wine you might well lose.¹

The change came from an unlikely source: a furnace. In early seventeenth-century England, a shift in how glass was heated produced a bottle so much darker, thicker, and stronger than anything before it that the French gave the material its own name: verre anglais, English glass. The man whose name became fixed to that bottle was not a glassmaker or a vintner but a courtier and natural philosopher, Sir Kenelm Digby.²

What wine lived in before glass

To see why a stronger bottle mattered so much, it helps to remember how little the bottle had counted for until then. From antiquity onward the working container for wine was the clay amphora and then, increasingly, the wooden barrel, which the Romans adopted from the peoples of Gaul and the Alps because it was tougher on the road and easier to roll onto a ship. Wine was a bulk commodity moved in bulk vessels, and the merchant sold it by the cask.¹

Glass had its place at the table, but it was a luxury of display. The great Venetian glasshouses of Murano made a clear, delicate cristallo that the rest of Europe imitated in the “façon de Venise,” and the results were dazzling and useless for storage. Thin-walled, light-coloured, and easily cracked, such glass could carry wine from the cask to the diner across a single evening, and no more. Nobody laid wine down in it, because nobody sensible would trust a year’s good wine to a vessel that might fail in a month.

The consequence was that wine, however fine, was essentially a young drink. It was made, shipped, and consumed within a year or two, its quality tied to the freshness of the barrel rather than to any patient improvement in the glass. The idea we now take for granted, that a wine might be sealed away and left, deliberately, to become something better with age, had almost nowhere to happen. It needed a container that would not fail over time.

An accident of policy: timber, ships, and coal

The container arrived through a decision that had nothing to do with wine. Early seventeenth-century England was worried about wood. The navy and the merchant fleet ran on timber, and the same forests that built ships were being burned in enormous quantities to fire furnaces — for iron, for glass, for anything that needed sustained heat. To the Crown, glassmakers stoking their ovens with oak looked like men burning the nation’s warships for a luxury trade.³

In 1615 King James I issued a proclamation forbidding the use of wood as fuel in glassmaking, reserving the country’s timber for shipbuilding and other purposes deemed more vital than drinking vessels. Glassmakers were forced onto coal, which England had in abundance. The change was meant as conservation policy. Its effect on the glass itself was transformative and entirely unplanned.³

Coal burns hotter than wood, and a hotter furnace makes a fundamentally different glass. To survive the higher temperatures and the coal-smoke atmosphere, English glasshouses adjusted their recipes, leaning on a higher proportion of sand and picking up iron and other impurities that tinted the finished “metal” a deep greenish-brown. What came out was denser and far stronger than the pale continental cristallo, ugly by the standards of a Venetian showpiece, but strong in exactly the way a storage vessel needs to be.² Much of the early progress belonged to large coal-fired works such as those of the monopolist Sir Robert Mansell, whose bottles were already noticeably tougher than the French could make.⁴

The unlikely knight

Into this picture steps one of the more improbable figures in wine’s history. Sir Kenelm Digby, born in 1603, was a Renaissance man in the fullest and least disciplined sense of the term. He was a courtier at the Stuart court and a diplomat; a privateer who in 1628 led a raiding voyage into the Mediterranean and won a celebrated skirmish against French and Venetian ships at Scanderoon; a devout and troublesome Catholic in a Protestant kingdom; and a natural philosopher curious about everything from astrology to the chemistry of plants.⁵

He was also, by any measure, a self-promoter and a collector of odd enthusiasms. He championed a “powder of sympathy” that was supposed to heal wounds by being applied to the weapon that caused them rather than to the injury. He left behind a posthumously published book of recipes, The Closet of the Eminently Learned Sir Kenelme Digbie Knight Opened, crammed with formulas for meads and spiced drinks. When the Royal Society was founded to put natural philosophy on an experimental footing, Digby was among its earliest fellows. He was exactly the sort of restless, moneyed, hands-on gentleman who might take a personal interest in how glass was blown.⁵

Digby’s furnace

Around 1633 Digby turned that interest into a workshop. Working with James Howell — a writer who had managed a glassworks and knew the trade from the inside — he set about making the coal furnace hotter still. The reported innovation was a matter of air: a wind tunnel drawing a fierce draught through the fire, raising the temperature beyond what an ordinary oven reached, combined with a glass recipe heavier in sand relative to the potash and lime that fluxed it.² Digby is said to have run a furnace in the Forest of Dean, at Newnham-on-Severn, from the mid-1630s, close to the coal that fed it.⁴

The bottle this process produced had a distinctive early form that collectors now call “shaft and globe”: a rounded, almost spherical body under a tall straight neck, in glass so dark it reads as near-black against the light. It was thick-walled and heavy, its base pushed up into a deep cone — the punt — that strengthened the bottom and gave the bottle a stable footing. A ring of glass, the string rim, was trailed round the neck to take the twine that held the cork. These features served durability rather than appearance.²

Why dark, thick, and heavy changed everything

Each of those homely qualities did real work. Thick walls could take the knocks of handling and cellar storage, and, as would soon matter enormously, could hold a wine that was building pressure inside. The dark glass shielded the wine from light, a cause of spoilage, so that a bottle laid down in a cellar was protected in a way a pale flask never protected its contents. The punt added strength where a flat base would crack. The result was, for the first time, a glass container you could actually trust with wine over the long term.

That trust unlocked a new practice: binning. A strong, uniform bottle could be laid on its side, corked tight, and stacked in a cellar, the wine kept in contact with a damp cork that stayed swollen and sealed. Wine could now be set aside on purpose and left for years, and, crucially, the year of a wine could be recorded and remembered, because the bottle that held it survived long enough for the vintage to mean something. The modern practice of fine wine, in which a bottle carries a date and is expected to improve, depends on a container tough enough to last that long.¹

The disputed credit

If Digby did all this by the mid-1630s, why is his authorship ever in question? Because the years that followed scattered him. The English Civil War made a Catholic royalist a marked man; Digby spent stretches abroad in exile and was for a time imprisoned, his affairs in disarray and his glasshouse out of his hands. In his long absences other men took up the strong-bottle trade and, in some tellings, claimed the innovation as their own.⁵

The matter came to a head in 1662, when the question of who had first made these bottles was put before Parliament, which found in Digby’s favour and recognised him as the originator. He enjoyed the vindication only briefly, dying in 1665. The recognition acknowledged priority; it was not a modern patent granting exclusive rights, and it settled a dispute rather than proving a clean act of sole invention.⁵

The real picture is less tidy than “one knight invented the wine bottle.” Strong English glass was the product of a whole industry pushed onto coal by government policy, with several works, Mansell’s among them, contributing to a bottle that grew tougher across a generation. Digby’s genuine contribution was to refine the furnace and, by force of reputation, to attach his name to a result that was already collective and industry-wide.⁴

1662, and the wine that sparkled

The year Parliament vindicated Digby happened to be a landmark for English wine in a second way, and the two facts are connected by the same strong glass. On 17 December 1662 the physician Christopher Merret presented a paper to the Royal Society, “Some Observations concerning the Ordering of Wines,” describing how vintners added sugar and molasses to their wines to make them, in his words, “drink brisk and sparkling.”⁶

This was a deliberate account of making wine sparkle by inducing a second fermentation in the sealed vessel, written down in England roughly three decades before the work usually credited to Dom Pérignon in Champagne. The reason it could be done in England first was the bottle. A wine fermenting a second time throws off gas, and a weak glass simply bursts. Only a vessel strong enough to hold that pressure without shattering could turn a fermenting wine into a sparkling one on purpose rather than by luck.⁶

Merret described making wine “drink brisk and sparkling” in 1662, and the method depended on English glass finally being strong enough to contain a second fermentation.On Christopher Merret’s paper to the Royal Society

It would be too much to say an Englishman “invented champagne” on the strength of one paper, and the sparkling wine of Champagne as we know it owes a great deal to later French craft in blending, riddling, and pressure control. But the enabling technology, a bottle that could contain the fizz, was English, and it was the same coal-fired strength that let wine be aged in the first place. Strong glass both preserved wine and gave winemakers room to experiment with it.

The shape keeps moving

Once the bottle could be trusted, its form began to evolve with unusual speed, driven by the practical demands of the cellar. The round shaft-and-globe of Digby’s day gave way, by the 1670s and 1680s, to the squat “onion,” broad-based and short-necked and hard to knock over. Through the early eighteenth century the body flattened and straightened into the “mallet,” and then, as binning took hold as standard practice, it stretched into the tall cylinder we still use, a shape whose whole point is that it lies neatly on its side and stacks in a rack, dozens deep, cork down and wine dark.¹

That final cylindrical form, arriving in the second half of the 1700s, completed the shift Digby’s furnace had begun. A strong bottle made ageing possible; the desire to age wine at scale reshaped the bottle until it was built for the rack; and the racked, binned, cellar-aged bottle became the physical basis of what we now mean by a fine wine with a vintage on it. The dark heavy glass that a Venetian craftsman would have discarded as a failure became one of the most consequential vessels in the history of wine.

What the strong bottle really changed

We tend to treat the wine bottle as a given, the neutral thing wine simply comes in. The verre anglais bottle was an invention with consequences, and the consequences ran in one direction: toward wine as something that could be kept, improved, dated, and prized. Before the strong bottle, a great vintage was consumed and gone. After it, a great vintage could be laid down, waited for, and sold years later at a price the young wine never commanded.

Kenelm Digby, restless and self-advertising to the end, would probably have enjoyed being remembered as the father of the modern wine bottle, even if he shared the fatherhood with a coal seam, a shipbuilding shortage, and a whole trade of anonymous glassblowers. The credit is not quite his alone. But the bottle was real, and so was the change it made: the cellar of laid-down wine, waiting on its vintage, begins with the strong dark glass that a fierce English coal fire made possible.

Related dates

Wine’s turning points are often buried in technology and trade rather than in the vineyard. Explore what else happened on this article’s date below.

Read more

The vessel has a long story of its own: trace the science, art, and history of wine bottle-making, see what wine travelled in before the green glass bottle, follow how bottle-making industrialised into a modern trade, and read the full history of Champagne and the bottle that carried it.

References

1. On wine’s long reliance on the cask, the fragility of pre-modern glass, and the rise of binning and vintage-dating once a strong bottle allowed cellar ageing: general histories of the wine bottle and of wine storage. ↩
2. On Sir Kenelm Digby’s coal furnace with a wind tunnel and sand-heavy recipe, the dark thick “shaft and globe” bottle, and the French term “verre anglais”: accounts of the English glass bottle and the “glass onion” lineage. ↩
3. On King James I’s 1615 proclamation reserving timber for shipbuilding and banning wood as glass-furnace fuel, forcing English glassmaking onto coal: histories of English glass and fuel policy. ↩
4. On coal-fired works such as Sir Robert Mansell’s producing bottles stronger than the French, and the collective, industry-wide character of the strong English bottle: accounts of seventeenth-century English glassmaking. ↩
5. On Digby’s biography (1603–1665) — courtier, privateer at Scanderoon, Catholic royalist, early fellow of the Royal Society, author of a posthumous recipe book — and the 1662 parliamentary recognition of his claim after wartime disruption: biographical accounts of Sir Kenelm Digby. ↩
6. On Christopher Merret’s paper “Some Observations concerning the Ordering of Wines” to the Royal Society on 17 December 1662, describing adding sugar and molasses to make wine “drink brisk and sparkling,” and its relation to strong English glass and to Dom Pérignon’s later work: histories of sparkling wine. ↩

Books worth reading

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The Knight Who Invented Champagne
Stephen Skelton MW
A focused account of Digby, the “verre anglais” bottle, and how strong English glass made bottle-fermented sparkling wine possible.

Inventing Wine: A New History
Paul Lukacs
A history of how wine became what it is, including the bottle and cork revolution that turned wine into something worth ageing.