Standing on the station platform, waiting for the Philadelphia train one night in the summer of 1902, Willis Carrier was about to have his 'eureka moment'.
As the fog rolled in across the track, he suddenly realised how he could fix the nascent air-cooling system he'd been working on, using water as a condensing surface.
This sudden moment of inspiration led to the invention of modern air-conditioning, a fortune for its inventor, and the foundation of a multi-billion dollar company.
The lone genius, beavering away in the seclusion of his lab is how most of us imagine the great moments of innovation have come into being. But is this really the whole story?
Not entirely, according to author Steven Johnson. He believes Willis Carrier is very much the exception rather than the rule.
"It's not that the individuals disappear in this, it's just that they need to be part of something larger than themselves to be able to do the work that they do."
This is not completely new ground for Mr Johnson. He has written seven books on how science, technology and human experience interact, including the best-selling Everything Bad Is Good for You: How Today's Popular Culture Is Actually Making Us Smarter.
He is the co-founder of three websites - the now defunct Feed magazine, Plastic.com and his current project: hyperlocal aggregator outside.in. He also has nearly 1.5m followers on social media site Twitter.
Isolation v collaboration
His latest book, Where good ideas come from: The natural history of innovation, is his attempt to explain the phenomenon of inspiration.
"[Good ideas] come from crowds, they come from networks. You know we have this clichéd idea of the lone genius having the eureka moment.
"But in fact when you go back and you look at the history of innovation it turns out that so often there is this quiet collaborative process that goes on, either in people building on other peoples' ideas, but also in borrowing ideas, or tools or approaches to problems.
"The ultimate idea comes from this remixing of various different components. There still are smart people and there still are people that have moments where they see the world differently in a flash.
"But for the most part it's a slower and more networked process than we give them credit for."
The book spans a huge period in history, ranging from the invention of double entry accounting, and Gutenberg's printing press in the 15th century, through to Tim Berners Lee and the world wide web, and ultimately YouTube.com.
He had the idea for the book while writing The Ghost Map, about the cholera epidemic of 1854 in London, and the subsequent discovery of the origins of the disease. The story goes that a man named John Snow had had the idea to map cases of the disease, and using that map pinpointed the source of the outbreak - a water pump.
As he researched the story he realised that it simply wasn't true - that Snow had had the idea for some time before this and that he also had had a collaborator, a vicar named Henry Whitehead who was central to the investigation. This is what Mr Johnson calls the 'slow hunch'.
"I realised there was this theory about innovation, and the spaces that made innovation possible, that was lurking in the background of that story"
The book starts with a young Charles Darwin on a sun-drenched tropical beach in the Keeling Islands, as he formulates his theory on the creation of these coral islands - not simply pushed up by volcanic forces, but the result of the work of millions and millions of tiny organisms - the coral itself.
He is at the beginning of the 'slow hunch' that would result decades later in his theory of evolution. The coral reef also provides Mr Johnson with his analogy for the perfect innovation environment - a hugely diverse eco-system where despite the constant competition for resources, existence is dependent on collaboration.
This could be a city, a coffeehouse, an environment where ideas come into contact with each other - as Mr Johnson puts it, a liquid network.
"You know I think that there are two [perfect reefs] that really stand out. Clearly the web itself has been an amazing reef. Just the speed with which it's transformed itself over the last 15 years is just amazing.
"And so much of that is because it's wonderfully set up for other people to build on top of other people's ideas. In many cases without asking for permission.
"But I think that the other thing I want the book to be a reminder of is how much important innovation both in the commercial space and the private space comes out of the university system.
Universities, Mr Johnson argues, have in many ways exceeded the market in terms of the pace with which they generate ideas - despite the lack of the 'direct reward' found in the commercial arena.
"I think there's this abiding belief that markets drive innovation, corporations drive innovation, entrepreneurs driven by financial reward drive innovation, and while that's certainly true in many cases there's also this very rich long history of important world-changing ideas coming out of the more or less intellectual commons of the universities.
"The internet was not commercially useful to most ordinary consumers for 30 years really. It was in a sense a 30-year-hunch. It was providing other services in that time but in terms of the ordinary consumer and the payoff for investment it took a long time.
One of the other great preoccupations of the book is the concept of the 'adjacent possible', a phrase coined by the scientist Stuart Kaufman. In essence it means that invention is dependent on the right circumstances - as in a chess game, where there are a finite set of moves available at any given time.
"You can't invent a microwave oven in 1650, it's just beyond the bounds of possibility. There are too many intermediate steps on the way to something that complex.
"So the trick is to find the points of possibility in your own particular place and own particular space. And not jump too far ahead. It's kind of an argument for small modular steps using the ingredients available to you and not trying to reinvent everything.
Building your reef
So what should companies be doing to foster innovation in their workforces? Mr Johnson argues that creativity is a continuous process.
"Part of the problem is that one day a year they have a corporate retreat and they all go into the country, and they do brainstorming sessions and trustfalls and then they go back to work.
"But equally you don't want to have a non-stop creative process where nothing gets done.
"Corporations have an opportunity to cultivate hunches and hobbies and the sideprojects of their employees because those are such great generators of ideas."
Google is one company that has famously capitalised on giving space for workers to innovate, with its 20% time system. Employees are required to spend 20% of their time working on their own pet projects.
According to the company, about 50% of new features and products have resulted from it, including Adsense, Google suggest and social network Orkut.
"One of the lessons I've learned is that so many of these great innovators, Darwin is a great example of this, one shared characteristic they all seem to have is a lot of hobbies."
"I mean the web was a hobby for Tim Berners Lee, that's one of the wonderful things about it, it was a side project at his job at Cern."
Mr Johnson's open, collaborative environment is the antithesis of the closed rooms of corporate Research & Development and the increasingly litigious world of the intellectual property lawyer. For some companies betting on the slow hunch that may pay off in 30 years may seem a risk too far.
But for those who yearn to find the spark within ourselves, Mr Johnson rounds off the book with this advice:
"Go for a walk; cultivate hunches; write everything down; but keep your folders messy; embrace serendipity; make generative mistakes; take on multiple hobbies, frequent coffee houses and other liquid networks; follow the links; let others build on your ideas; borrow, recycle, reinvent."