Boom (Poof).

The first word of today's explosion came from the fire safety director of the building, a man whose voice we are generally equipped to ignore. After a series of alarm tests over the past day-and-a-half, we were prepared for notice of further interruptions, or perhaps, signaling the conclusion of some undisclosed and unnoticed diagnostic, a completely unnecessary invitation to "please resume normal activities."

Instead the piercing screech was followed by a brief account of an explosion on 42nd street, currently under investigation, and a suggestion that we not try to leave the building. Strangely, this was delivered in exactly the same slow and confused-sounding monotone that has characterized every other fire safety announcement, both in our current offices and in the previous building.

I saw the smoke through one of the downtown-facing windows and was immediately self-conscious about having cursed, loudly, in the office. I guess we should have recalled that smoke is typically, dark, not white, papal selection being the obvious exception. This smoke was almost cloud-like. All that struck us, though, was the size of the plume, its billowing up and out and roiling the skies. Cell phones came out, and the circuits were quickly jammed. It may have been just me, but I forgot temporarily about the existence of my office line, instead spending minutes staring at my handset, waiting for it to connect.

We decided to partially evacuate, get lower in the building and be better prepared to leave should the need arise. Some wanted to go right away, but I felt, illogically, like gathering my things and making some phone calls. By this time I'd remembered my landline. Maybe I was more confused and disturbed than I felt at the time.

Somebody went around with news that an early report from Bloomberg (the station, not the mayor) had made reference to a bomb, and that spooked people, though really it was what we all expected. Despite the news, in this second phase people seemed to calm down a bit, and some who had been heading for the stairs lingered. We changed the television from MSNBC to the local news. There was still no word.

The fire safety director set us at ease, coming on to say, in his inimitable and excruciating style, that the problem had been traced to an exploded transistor (this, it turns out, is not true - it was a blown steam pipe). There was a palpable sense of relief. We were about to resume our regular activities, when we were requested to leave the building.

Outside, many many cell phone cameras, and the surprisingly loud roar of vapor pouring out of the street.