PORTSMOUTH, R.I. -- When last seen four months ago, Jim Dickson was wandering around Washington with half a pocketful of money and a far-fetched dream. Now, the dream is reality and he must decide: Sail alone across the Atlantic or put it off until next year, or maybe forever.

Crunch time. "I feel like a manic depressive," he said. "One moment, I'm high as I've ever been. I know I can make it. The next, I don't see how I can get everything done. I go up and down like this about six times a day."

"Why couldn't you do something simple, like a bicycle trip?" wondered his friend, Renee Brereton.

"Bicycle trip?" he roared. "I'd probably get run over by a truck."

The fact is, nothing is simple for Dickson, who has been tilting at windmills since he went blind from a progressive eye disease at age 7.

Now 41, he's left his job with Project Vote in Washington, set aside a degree from Brown University and a career of public-interest organizational work to spend a year on something "completely self-indulgent," as he puts it.

Self-indulgent? A blind man sailing across the Atlantic in a 36-foot boat?

"It is, compared to what I've been doing," Dickson said. "Every job I've ever had has been for a greater purpose. Sure, I'm trying to prove something with this trip, but I'm also doing it for the fun of it, just to be messing around in boats."

In March, when he first plotted his scheme for a story in The Washington Post, Dickson was a pale, bearded, bureaucratic-looking character with a little 23-foot sloop tied up at frigid Washington Sailing Marina, a smattering of small-boat sailing experience, $90,000 of his $150,000 budget and some rough plans to drum up the remainder through donations.

Now, suddenly, the planning is over. His new, 36-foot Freedom sloop, Eye-Opener, lies at slip E1 in Bend Boat Basin, sparkling white and rigged for offshore work. Dickson, who's been living aboard, bounds out of the hatch like an old salt and scampers sure-footed down the tippy floating docks to greet a visitor.

"Come on aboard," he says, his bald head burned nut-brown by the sun, his jeans bleached sailor pale.

Is he ready?

"At this point, I'm about 65 percent sure I'll go," said Dickson. His drop-dead date is around July 20, after which he'd risk too much danger of storms in the English Channel. It's now or never, at least for this year, and it's a ticklish situation.

Advisers counseling him recommend caution. Most think he should wait a year. Meanwhile, the "Today Show," "CBS Evening News," The Post and the Providence Journal are running stories, pestering him for final word.

The pressures to deliver are considerable. Only Dickson can decide whether the rewards merit the risk. It's a big ocean. A man could disappear out there.

"I think his chances are very good, really," said 'round-the-world racer Francis Stokes, dean of American single-handers. "I asked him how much he valued his skin and he said, 'Quite a bit.' That's a good answer.

"He has a very sound boat. I believe his survival chances are excellent. Whether he'll accomplish what he's set out to do {reach Plymouth, England} is another matter.

"He's got an awful lot of equipment to learn to use, which is a good argument not to go this year. I've already kind of made the suggestion to him to wait until next year.

"I wouldn't hesitate to give him my advice not to go, but whether he'd take it, I don't know. With such a good boat, I think he could pull it off."

How does a blind man go about sailing across the Atlantic?

Very carefully.

"If we get a storm and the wind gets to 40 knots, I'll just drop all the sails and go down below and wait," said Dickson. "When the storm is over, I'll go back up and figure out where I am. I'm in no hurry."

And though he's sailing alone, he'll have someone to chat with.

"Greetings, Capt. Dickson, I am SVEN, your Shipboard Voice-Enhanced Navigation System."

The computerized voice, eerie and mechanical against the mellow backdrop of halyards slapping the mast, comes from a speaker mounted below the tiller.

SVEN is Dickson's lifeline, giving him data audibly, since he can't see the readouts on the satellite navigation monitor, which tells him where he is, or the depth-finder, the wind speed, boat speed or wind direction indicators and a host of other instruments.

SVEN connects to a computer that monitors all electronic data-gatherers on the boat. All Dickson has to do is dial up the information. It all works superbly at the dock.

But at sea? "We all know about electronics and salt water," said Tony Lush, veteran of several solo transatlantic crossings and the BOC 'round-the-world single-handed race.

"To be honest," said Lush, "he's got everything you need to get across the ocean. But he has a long way to go mentally in terms of familiarity with his equipment and experience on the boat. And he needs more redundancy" in case the electronics go dead.

Where will he turn if SVEN drops dead? Dickson hauls out a hand-held braille compass, its numbers raised to feel by hand.

It looks tiny and unpromising, gauged against 2,500 miles of sea.

A sailor preparing for a sea voyage checks his boat the way a rock-climber checks his knots. There are things you don't entrust to anyone else.

But for Dickson, the luxury of personal inspection is impossible. "I would have loved to help them install the generator," he said, "but if I had, it would have taken twice as long and the cost would have been double."

So the generator is in and Dickson has to hope it's right. When it began spewing water during a sea trial recently, the floorboards were awash before Dickson tracked down the faulty cooling valve with help from a friend on board, Stokes said.

If it breaks at sea, he'll have to figure out why on his own, by feel, never having worked on it intimately before.

Last weekend, a crew from Tillotson-Pearson boatbuilders, who prepared Eye-Opener, fitted a new mast. Dickson wanted to help, but it was late on July 4 weekend and the rigger wanted to get home.

"Look," said the exasperated workman as Dickson hung over his shoulder, "there's two ways we can do this job. I can do it alone and you can have a boat to sail this weekend, or we can do it together and finish sometime next week."

It's frustrating. Dickson had hoped to have at least 500 hours sailing time in before embarking. By last weekend, with all the outfitting delays, he'd sailed only 150 hours, mostly in protected Narragansett Bay, usually with Jamie Bennett, a local sailor.

Bennett's assessment? "If I didn't think this trip were worthwhile and feasible, I wouldn't put all this time into it. As far as him going, I don't have any fear of it. In fact, I'm envious."

So there it stands: Blind man against the trackless wastes of the Atlantic; some saying go, others saying wait.

Practically everyone involved has the same things to say about Dickson: Intelligent, they agree, brave, and just stubborn enough to pull it off.

But he's blind. The intricate web of gadgetry that makes a sailboat go remains largely a mystery to him. He can track things with his hands and with his facile mind, but mysteries run deep when you can't see them. Mechanics? "He's just not tuned into that sort of thing," said Stokes.

Has he the adaptability to deal with surprises at sea, with the wind howling, the boom clattering and crashing across the deck, sheets of green water cascading into the cockpit and SVEN silenced by corrosive salt water?

"The way I see it," said a transatlantic veteran, "he has about a 90 percent chance of riding the westerlies across without a hitch and arriving in England a hero.

"The one-in-10 chance is that the electrics go wrong, in which case he has to get on the radio and call for help, or he hits a big storm and can't react quickly enough. Then, he either loses the boat or he pulls through.

"It's the chance you take."

Crunch time.