Standing in St Peter's Square, I had a flashback to 1978.
All eyes upward - crowds gaze towards the chimney
The first wisps of smoke appeared from the chimney above the Sistine Chapel against a darkening sky.
There were screams from the huge crowd, and people began to applaud wildly.
"It's white, it's white," they yelled, pointing at the chimney.
Then, the smoke started to look a little grey. The roars of delight were replaced by a buzz of confusion.
Peering at the chimney through my binoculars, I could see the smoke turning blacker by the second.
In the crowd, delight turned to disappointment, and the absence of Vatican bells confirmed our suspicions.
The first ballot of the 2005 conclave had been indecisive. No white smoke, no pope.
It was all horribly familiar. I witnessed the two conclaves of 1978, and the smoke caused no end of trouble.
One minute it looked white, the next black. It often ended up a shade of grey, which caused consternation.
To be fair to the Vatican, the confusion tonight only lasted a couple of minutes, but it suggests the cardinals have not quite got the hang of the smoke signals yet.
The addition of chemicals is supposed to remove all doubt about the colour.
But at dusk, with the light fading, your eyes can play tricks on you.
"I thought it was white and I started clapping and cheering," admitted Father Carlos Bambi from Angola.
"I am a little disappointed, because I thought we would have a new pope today. I have to fly home on Wednesday, but I will be back here tomorrow."
Despite the anticipation, none of us had really expected white smoke so quickly.
The option of holding a single vote on the first day of the conclave was introduced by John Paul II.
I suspect he wanted to give the cardinals a chance to gauge the support for various candidates, before getting down to the serious voting on Day Two.
The mood of the crowd in St Peter's Square on the conclave's first evening was quite different to the atmosphere when people gathered here to pray for John Paul II.
Then, there was sadness and a quiet resignation, as everyone was aware his life was ebbing away.
Now there is a sense of excitement at the thought of a new pope stepping out onto the balcony of the basilica.
"I came here two hours ago, straight from the airport," said Mario Rivera, an advertising executive who had flown in from Honduras.
"This is my first chance to see a pope being elected, and I will be here every day and every night until I see white smoke."
There is a chance the smoke could signal the election of Cardinal Rodriguez Maradiaga of Honduras.
Father Juan Angel Lopez used to work for the cardinal, but insisted that the nationality of the next pope was not important.
"It would be wonderful for my country if they choose Maradiaga or another Latin American, because we would have a pope who understands our way of thinking."
A few feet away, draped in the flag of Venezuela, was Hernan Arecena, a 19-year-old student.
Modern methods for capturing an ancient ritual
"History is being made here, so it is important to come here and watch it," he said, smiling.
"I just want a good pope. But if the best pope is Latin American, I will be happy."
Among the many flags in St Peter's Square I spotted the Stars and Stripes.
John Paul Sonnen from Chicago was born in 1979, and named after the pope.
"The world is ready for a black pope, and I think the time is now," he told me.
"I have put everything on hold. I will be here every day and every night until we have a new pope. You can't pass up this kind of thing."
The cardinals, locked in conclave and cut off from the outside world, cannot see the reaction of the crowd.
If it was possible to contact them, I would pass on a request from those of us who watch and wait in the square - please work on those smoke signals.