Books, is it. And money. There is money to be made if you can produce the right book at the right time, but the whole thing is dictated by fashion, and it's a fickle business.
Dava Sobel hit the right note a couple of years ago with her book on longitude, sensibly called Longitude. This prompted me to approach a whole slew of publishers with the first two chapters of my book on latitude, provisionally entitled Latitude. But I was too late: already, the bottom had fallen out of the historical marine navigation books market.
It's all about identifying a particular trend and then moving very fast. The food book market, an enormous money-spinner, is now almost entirely in the hands of Delia Smith, though there may be a useful spin-off in my upcoming Guide to Celebrity Chefs, if I can keep it to one volume.
Similarly, the gardening book market has never been so healthy, buoyed up like the food book market by its own collection of TV gardener personalities.
However, in this area a lucrative subsidiary market has begun to emerge, namely the flower book.
The big book of the last few weeks is about the tulip. It is called, not surprisingly, The Tulip. Written by Anna Pavord and retailing at £30, it is selling very well indeed, and is already being serialised on Radio 4.
All of which explains why I am working flat-out on my book on the dandelion, negotiating a reading deal with Today FM, and inviting bids for the film rights. Like Anna Pavord's book, The Dandelion* will be a work of immense scholarship, though not quite as richly illustrated as The Tulip, which has beautiful colour pictures of the numerous tulip species on just about every page. This is not because my publisher won't spend the money, but because there is actually only one species of dandelion, and a perfectly good picture of it will grace my book's cover.
However, I have tried my best to write as lyrically about this single species as Ms Pavord has written about the T'zenaide tulip, for example - with yellow flowers that are "elegantly waisted, the top third of the flower flipping outwards". The dandelion, I have noted, "has a green stem and a yellow head and that's about it". Regarding the origins of the word "tulip", Ms Davord spins an exotic tale involving a Flemish ambassador to the court of Suleyman the Magnificent in 16th-century Constantinople, and a delightful misunderstanding between a couple of Turkish words.
Fired by her story, I began looking into the history of the word "dandelion". Excitedly presuming it might have something to do with an obscure French gardener, perhaps by the name of Dan de Lyons, I imagined a heartbreakingly romantic life for him. He might turn out to be a lonely recluse unfairly dismissed by his aristocratic employer for unspecified incidents involving pedigree peacocks, but ultimately redeemed by his cultivation of the first dandelion in the gutters of Lyons. Who could tell?
So I spent three weeks researching in the elegant French city. Unfortunately, I found nothing to support my theory. So I left. Returning home, I looked at, and into, the word "dandelion" for ages. Then I looked at lions around the world, and then at Dans around the world. It was all to no avail. Then one day I checked my pocket dictionary to discover that the dandelion got its name from the Old English word "dandelion", meaning dandelion.
At least that mystery was solved. My dandelion research findings were not as thrilling as Ms Pavord's tulip discoveries. Unlike tulips in years gone by, dandelions rarely fetched high prices on world markets. No dandelion ever fetched as much as an Amsterdam town house, or even a town mouse. In fact, there is no record of anyone ever paying anything for a dandelion.
The dandelion was never the plaything of the rich. No great Dutch artist, and not even a Saturday morning bargain-price street artist, ever painted a dandelion as if it were a society hostess. No financial crisis ever marked the end of dandelion mania, for the very good reason that no dandelion mania ever existed. No one tells intriguing historical tales about dandelions, or any tales at all.
If an extended essay in flower powerlessness is what you have been waiting for, you will find The Dandelion unputdownable.
* Secker & Warburg, 1,350 pages, £45, this autumn.
