Intro
Lawrence Hamtil presents a history of Corning, the advanced glass, ceramics and optical physics company, running from post-Civil War railroad signal lenses to the fiber optic cable now going into the AI build-out. Douglas Ott and Devin LaSarre press him on the Houghton family's management, on how the company spent through the dot-com collapse, and on a 1918 headlight advertisement Ott dug out of archive.org.
Host: Lawrence Hamtil, co-founder and principal at Fortune Financial Advisors, who presents the episode
Also on: Devin LaSarre, private investor and author of The Invariant Newsletter, and Douglas Ott, founder and chief investment officer at Andvari Associates
Published: 28 August 2026 on Preferred Shares Podcast
Show notes | 36 min
Key Takeaways
Corning is a light company that happens to make glass
"Corning is not necessarily a glass company. I mean, certainly that's what the company is known for, but it's also a light company." — Lawrence Hamtil
Automating the light bulb is what stopped General Electric taking the business in-house
"it became possible to make hundreds of thousands of bulbs in a day in a factory, whereas before, by hand, they might make 100 bulbs in one hour with one skilled glassblower" — Lawrence Hamtil
R&D spending hit its high after the dot-com and telecom bubbles burst, not before
"in 2002, research and development as a percentage of revenues reached 16%, which was about the highest point from 1991 through to today" — Lawrence Hamtil, on a stretch that also saw the stock "drop more than 90%"
Corning left the television bulb business because its customers lost, not because its glass did
American set makers gave up share to Sony and Panasonic, and Corning exited with them
Gorilla Glass sat in niche heavy-duty uses for four decades until the iPhone
Steve Jobs went to Corning after his keys scratched his prototype phone, on the story Hamtil tells
The 1970 proof that glass could carry a signal without degrading it is the whole fiber franchise
Donald Keck, Robert Maurer and Peter Schultz did the work; the demand arrived half a century later
When General Electric gave up on the big telescope lens, Corning took the job and the prestige
Corning bought its way into medical testing and then spun it out as Quest Diagnostics
A company can be relevant to the same industry twice
Out of television tubes by the 1960s, back in through the fiber that carries the picture
A second episode on Corning's business today is coming, with Morningstar's Will Kerwin
Not a Glass Company, a Light Company
Hamtil's primary source is The Generations of Corning: The Life and Times of a Global Corporation by Davis Dyer, published in 2001. He calls it dated but comprehensive, with "tons of great history"
The book's opening framing is the one that stuck with him: "Corning is not necessarily a glass company. I mean, certainly that's what the company is known for, but it's also a light company."
His reason for liking it: "in many cases, glass is nothing without the light that passes through it"
The distinction, in Hamtil's reading, separates what the company sells from what it is actually for, and changes how an investor thinks about its research and development
Devin LaSarre opens the episode by saying most listeners interact with Corning's products daily without thinking about it. Hamtil runs the list: fiber optic cable behind an internet connection, Gorilla Glass under a thumb, Pyrex or Corningware in a kitchen that would otherwise be using earthenware
From Bay State Glass to Corning, New York
Founded in 1851 by Amory Houghton Sr. in Cambridge, Massachusetts, as the Bay State Glass Company
Moved to Brooklyn, then to Corning, New York in 1868, where it became the Corning Flint Glass Company
Incorporated as Corning Glass Works in 1875, and took the name Corning Incorporated in 1989
The first major innovation was corrugated railway signal lenses in the post-Civil War era, when railroads were the center of the economy
Red lenses faded outdoors under dust and grime, which made railroad operations increasingly dangerous
The founder's son, Amory Houghton Jr., was a tinkerer who experimented with adding copper to the glass composition and produced a deep ruby-colored glass that could be seen from much further away
They also made the outer surface concave and very smooth so it would not collect dust and grime, which Hamtil says seems obvious now but was not common practice at the time
The Ribbon Machine and the Fight to Keep General Electric
Thomas Edison's light bulb was the next opening, around the turn of the century, and it immediately exposed a manufacturing problem: glaziers blew bulbs by hand, and lighting large cities meant tens of thousands of bulbs
Labor unions were gaining force, American glassworks were losing competitiveness against European rivals, and the cost of hand-blowing bulbs was weighing on Corning
General Electric and others were tempted to pull the work in-house, and Corning was at risk of losing a major customer and a huge market
In the 1920s, two Corning engineers, William Woods and David Gray, built what became known as the ribbon machine
A continuous belt of poured glass passes over a perforated metal plate, and compressed air forced through the holes blows the bulbous shape
Hamtil tells listeners to look up a video of one running rather than take his description for it
"it became possible to make hundreds of thousands of bulbs in a day in a factory, whereas before, by hand, they might make 100 bulbs in one hour with one skilled glassblower" — Lawrence Hamtil
General Electric and the rest could not compete economically with that, so Corning kept the business. Hamtil's read is that the culture of research and development was already visible this early, aimed at making products widely accessible rather than only better
Pyrex, Corningware and the Accident That Made Pyroceram
Pyrex came early in the 20th century, building on the railroad lens work
Before glassware, kitchens ran on earthenware pots and cast iron — hard to clean, easy to break, in an era before dishwashers and before most houses had running water
Pyrex went into tens of millions of American households and became a staple of American cooking
Corningware followed as a major consumer hit, not transparent but a very durable ceramic material, developed by Corning researcher S. Donald Stookey
"he had left some experimental glass in an oven that overheated. But instead of melting, it became more of a ceramic material." — Lawrence Hamtil, relaying the story as it is told
It could take extreme heat without cracking or distorting, and Hamtil says dropping it on the floor was likelier to damage the floor
The material's other name is Pyroceram, and its heat resistance made it the military's material of choice on missiles, which had to hold their integrity through launch and through an atmosphere that gets extremely hot
RCA, Television Bulbs, and the Customers Who Lost
By the 1930s the growth market was communications: wireless radio was a hit and television was in its infancy
Corning was a primary supplier to RCA, then one of the most important companies in the country, and effectively the exclusive supplier to the television manufacturers
The television bulb business was a cash cow until roughly the 1960s, when it ended for reasons that had nothing to do with Corning's products
"not because of anything that they had done, but because American TV manufacturers had begun to lose market share to Japanese competitors like Sony and Panasonic, who offered superior quality at lower prices" — Lawrence Hamtil
Corning exited the television bulb business altogether
Hamtil's summary of the first hundred years: the company sat at the cutting edge of railroads, electrification, consumer goods and communications in turn
The 1918 Conaphore Advertisement Douglas Ott Found on archive.org
Douglas Ott went into the archive.org holdings and turned up a 1918 Corning Glass advertisement for the Conaphore, a special glass cover for automobile headlights
The episode's aside on why that mattered: highways were not well illuminated at the time, and a driver was responsible for his own light
On the advertisement's account, the Conaphore neither scattered light in all directions the way other methods did nor dumped it directly in front of the car, but directed it where it was most effective and threw a long, broad beam ahead
The mechanism was a series of patented corrugations on the inner surface of the glass fixture, which bent the beam down
The chemistry did the rest: the composition was altered so blue and violet rays were filtered out and only the yellowish light passed through
"the blue and violet rays were the chief cause of the back glare because they are easily diffused by fog or dust particles" — Douglas Ott, reading Corning's own claim
Ott offers it back to Hamtil as an early, lesser-known product that makes the light-company framing concrete
Everything Is Chemistry, Everything Is Physics
"I'm known for saying everything is chemistry" — Lawrence Hamtil, on mixing copper into glass to get a better lens
His addition: everything is also physics, because bending the beam is the other half of the problem
These are not commodity products, in his framing. The research behind them creates innovations that both improve existing industries and let new ones develop or expand
Hamtil's recurring theme, offered as an aside rather than a claim about Corning specifically, is that conflict has helped American companies
"Corning had faced a lot of competition from German competitors up until World War I. Well, when World War I occurred, the U.S. was cut off from German glass products for obvious reasons." — Lawrence Hamtil
Corning filled the gap, which insulated it from foreign competition and pushed it to the front of the industries it was in
MetPath, Quest Diagnostics and the Turn to Fiber
Corning diversified into healthcare diagnostics in 1982 by acquiring MetPath
The logic was adjacency: Corning already made specialized glass laboratory equipment, and "owning the testing altogether seemed like a way to smooth out the more volatile areas of the glass business"
Some 15 years later the telecom industry had been deregulated and the internet age was arriving, and Corning decided that was where the company's future was
It reversed course and spun off the medical testing unit, which is today Quest Diagnostics
Hamtil's aside: prominent public companies frequently trace back into other existing companies this way
Fiber Optics, From a 1970 Proof to the Data Center Build-Out
The fiber business became a key focus in the 1990s, but it traces to 1970 and a team of Corning scientists — Donald Keck, Robert Maurer and Peter Schultz
"proved that light could carry information through glass without degradation of the signal along the way" — Lawrence Hamtil, on what that team established
The promise was a lightning-fast way to move information without needing ever more copper wire as the world got more connected
Fiber is now the backbone of the information economy and carries the vast majority of the world's data, with a place in the AI economy and the data center build-out
The technology is close to 60 years old, and Hamtil's point is that it is only now bringing the world fully into the information age — sometimes an innovation takes a long time to have its full effect
"you can kind of think of Corning as a glass company, but it's pretty much an infrastructure company for the information economy" — Lawrence Hamtil
Gorilla Glass and the Scratches on Steve Jobs's Phone
Gorilla Glass goes back to the 1960s, and like fiber it sat for decades in niche heavy-duty uses
The iPhone in 2007 is what changed it. "Steve Jobs famously had put his phone in his pocket, as the story goes. And he found out that his keys were scratching the surface of his phone." — Lawrence Hamtil
Jobs went to Corning and asked for a prototype thin enough and small enough for the phone, and Corning delivered it
Hamtil starts to say every touchscreen device owes its existence to Corning, then pulls the claim back to something he will defend: the scratch-resistant surface is what made navigating by hand practical instead of a mouse or another interface, and made those devices as widespread as they are
The Lesson: Spend More on Research When the Stock Collapses
Hamtil's primary takeaway from the whole history is that a company has to keep investing in innovation, new products, new applications for existing products and new materials
After the dot-com and telecom bubbles burst and orders failed to materialize, Corning doubled down rather than cutting back
"in 2002, research and development as a percentage of revenues reached 16%, which was about the highest point from 1991 through to today" — Lawrence Hamtil
"even in this major downturn, which saw the stock price drop more than 90%" — Lawrence Hamtil, on the same stretch
Corning was very rarely caught flat-footed when something threatened its business, on Hamtil's reading of the record: General Electric threatened the bulb business and Corning made bulbs faster and cheaper; German firms threatened the consumer business and Corning came back with Pyrex and a new way to cook
"that's something that has been consistent throughout its history, which is getting close to 200 years now" — Lawrence Hamtil, on the pattern of reinvestment
Devin LaSarre's addition is that the willingness is cultural, not defensive
Corning invests where it cannot fully define the opportunity or size the addressable market, not only where it can see a competitive threat
"a prime example would be in fiber optics where we're still seeing kind of this S-curve unfolding for this company from technology that was predicated on iterations from long ago" — Devin LaSarre
When General Electric Stumbled on the Telescope Lens
Hamtil's second lesson: a competitor's failure is an opportunity
"So a famous story of the Hubble telescope, which was being assembled in the 1930s." — Lawrence Hamtil, introducing the episode's telescope story
General Electric had the original design work for the telescope's lenses, and nobody had made pieces of glass that large before
The hard part was the cooling. Heating the glass, pouring it, forming the shape and then getting it to cool at close to the same rate throughout so it would not crack
"And eventually, General Electric, which is one of the great companies of all time, failed. They couldn't solve this puzzle and they dropped out. And so Corning stepped up and they seized the opportunity." — Lawrence Hamtil
Corning worked out an arrangement of the poured glass that let it cool systematically, and contended with a flood at the plant while doing it. The finished lens shipped across the country to California
The prestige was the real payoff. Persevering through it made Corning look like a high-technology company in a way it had not before, and Hamtil says it brought in more business
His last lesson is about perception: it is easy to judge a company by the products you happen to use, and miss the research, the scientists, the trial and error and the failed projects behind them. Investors have to be patient with new ventures, because a company living off its legacy cash cows is being short-sighted
What the Book Doesn't Cover: The Houghtons and Outside Talent
Douglas Ott asks whether the book deals with management across the generations. Hamtil says it covers the Houghton family and how they ran the company, but not capital allocation or the nitty-gritty
It reads as a contemporary view of the company through successive periods of American history, tying the innovations to the period
"It's not so much a business book as it is sort of a history book." — Lawrence Hamtil
For the analytical view, Hamtil points to a Harvard Business Review case study on how Corning navigated the dot-com collapse — investing through the downturn and preparing for the recovery rather than just surviving it
The company was family-run for most of its history, and the Houghtons now own very little of it
Hamtil raises the contrast with The Great A&P, the subject of an earlier episode with its author: A&P foundered because it never cross-pollinated with other entities, and lost its vision once the two brothers running it were gone
Corning could have ended the same way a hundred years ago and did not, because it brought in outside talent alongside internal promotion and made itself an attractive place for high-level chemists and physicists, which fed the breakthroughs
Hamtil's characterization is a company that is never satisfied with its own success, and he notes how few companies manage to disrupt themselves
Out of Tubes, Back Into Television
Douglas Ott's observation closes the loop on the television business: "Talk about going from the tubes and getting out of the tubes business, but now they're back in a different way. They're providing the fiber optic cables that transport the data to your TV."
Hamtil agrees: the company found a different way to be relevant to the same market
Ott then reads from a recent Wall Street Journal article on the pace of fiber production
"it took Corning nearly half a century to produce a billion miles of optical fiber. The second billion took eight years" — Douglas Ott, quoting the Wall Street Journal, which added that the next billion would probably arrive much sooner
Devin LaSarre's response is that this is an acceleration, and that the shape is a J-curve rather than an S-curve
This episode was meant as a brief history, and a second part is coming. Hamtil says they will interview Will Kerwin of Morningstar, who covers Corning, about the current product line, the competitive advantages and the company's prospects. Kerwin was on the show last summer
Hamtil's bottom line is that Corning's edge was never the glass itself but a willingness to keep funding research when there was no visible market and no reason to, which is why a company that started with railroad signal lenses now sells the cable the information economy runs on: "The story of modern American industry can almost be told through the lens, no pun intended, of Corning's own history."
Products, Companies & Tools Mentioned
Corning (The subject of the episode — advanced glass, ceramics and optical physics, and in Hamtil's framing an infrastructure company for the information economy rather than a glass company)
The ribbon machine (The 1920s Corning invention that automated bulb making and kept General Electric from taking the light bulb business in-house)
General Electric (Twice a rival — the customer that nearly integrated backwards into bulbs, and the company that failed at the big telescope lens Corning then delivered)
Pyrex and Corningware (The consumer breakthroughs that replaced earthenware and cast iron in American kitchens, and reached tens of millions of households)
Pyroceram (The accidental ceramic behind Corningware, so heat-resistant the military used it on missiles)
Fiber optic cable (Proved possible by Corning scientists in 1970 and now the backbone of the information economy and the AI data center build-out)
Gorilla Glass (Developed in the 1960s and stuck in niche uses until Apple's iPhone in 2007)
Apple and the iPhone (Steve Jobs asked Corning for a prototype thin enough for the phone after his keys scratched the screen)
RCA (The television customer Corning supplied when the set business was a cash cow)
Sony and Panasonic (The Japanese manufacturers whose quality and price took share from American set makers, which ended Corning's television bulb business)
MetPath and Quest Diagnostics (Corning's 1982 move into diagnostics, spun off some 15 years later and now a public company in its own right)
Morningstar (Will Kerwin covers Corning there and is the guest for the second part of this story)
Books & Resources Mentioned
The Generations of Corning: The Life and Times of a Global Corporation – Davis Dyer (Hamtil's primary source, published in 2001; comprehensive on the history but, in his words, more a history book than a business book)
A Harvard Business Review case study of Corning (Where Hamtil sends anyone who wants the analytical view of how the company was run through the dot-com collapse)
A 1918 Corning Glass advertisement for the Conaphore headlight lens (Douglas Ott's find in the archive.org holdings, and the episode's best illustration of Corning as a light company)
A Wall Street Journal article on optical fiber production (The source of the billion-miles-of-fiber comparison Ott reads out)
The Great A&P – Marc Levinson (The subject of an earlier Preferred Shares episode, used here as the counter-example: a family firm that never cross-pollinated and lost its vision)
A video of a ribbon machine in operation, on YouTube (Hamtil tells listeners to watch one rather than rely on his description)
Corning's own website (Carries the detail of how the telescope lens was finally cooled without cracking)
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