Every once in a while, the stock market seizes our attention. It did so Thursday, July 12, when the Dow Jones industrial average rose nearly 300 points, heading toward 14,000. Wall Street broke onto the evening newscasts and back into the minds of investors.

Why did prices soar that day? Nobody knows. Most of its big moves not only are impossible to predict, but can’t be explained even after they occur. And here’s the interesting part: Far from being a problem, that mystery is key to the market’s appeal. We’re drawn to Wall Street the same way we’re drawn to a spinning roulette wheel, an untested thoroughbred, or a stormy lover.

An exciting stock market energizes the overall economy, argues Aaron Brown, a Wall Street risk manager who wrote a 2006 book called The Poker Face of Wall Street. He points out that intraday trading serves little purpose other than entertainment. The market could simply accumulate orders and execute them at a single price at the close. But that would take away the fun, wouldn’t it?

The market’s leap on July 12 is a classic example of how a rally can emerge as abruptly and inexplicably as a row of cherries on a slot machine–generated not by economic fundamentals but by the inner workings of the market itself, including the volatile emotions of traders and portfolio managers.

Before the market opened that day, there were few hints that the Dow was about to rise more than 2%, the biggest jump since April, 2005. Stocks were trading higher in Europe, but they had fallen overnight in Tokyo. Wal-Mart Stores Inc. ( ) announced a slightly bigger-than-expected gain in June sales. A $38 billion deal by Rio Tinto ( ) to buy Canada’s Alcan ( ) raised speculation about a takeover of Alcoa ( ), a component of the Dow industrials. And the government reported a healthy gain in U.S. exports.

So conditions were good, though not great. Stock index futures were up in pre-opening trading, and when the New York Stock Exchange ( ) rang the opening bell at 9:30 a.m., prices rose to close the gap. Within minutes, the Dow jumped 80 points from its Wednesday close. It then climbed steadily through the morning without much additional news to go on except a drop in oil prices. The market flattened for a couple hours, and then around 2:30 began a powerful rally that lasted until just before the 4 p.m. close–even though by then oil prices were heading back up. “When the market has a bullish sentiment, it turns every piece of news into a positive,” says Peter Cardillo, chief market economist at Avalon Partners. “Even the negative news becomes a positive factor.”

Don’t even try to explain why the mood of Wall Street suddenly turns buoyant for a day. Says Peter L. Bernstein, the author and market strategist: “I have been in this business over 50 years, and I have never understood why all these people on one particular day get up with one thought.”

For investors who like big hits, what’s intriguing is that a handful of days like July 12 account for almost all of the annual returns from stocks. For example, in an analysis for BusinessWeek, Morningstar Inc. ( ) calculated that if you missed the 10 best trading days of 2007 through mid-July, your total return from the Standard & Poor’s 500-stock index would have been -3% instead of 10.5%. (If you missed the 10 worst days your return would have been 30%, but gamblers tend to focus on the upside.)

Explicable or not, days like July 12 loom large in the psyche of all market participants. For buy-and-holders, they make up for the down days they know they’ll suffer through. For players, they’re the big wave you don’t want to miss. In either case, the lure of July 12 for investors is the same: You gotta be in it to win it.

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Carl Icahns failed attempt to buy Lear may ultimately prove to be a win-win situation for the billionaire investor.

If Icahn had completed the acquisition, he would have paid $37.25 a share, little more than the $37.03 average price of the automotive-seat makers stock since its initial public offering in 1994. After shareholders rejected the proposed $2.9 billion takeover, the stock rose well above the offer.

Nobody benefits more when Lear advances than Icahn, who holds a 16 percent stake. The investment has produced a gain of $224.1 million, judging by the total cost cited in a regulatory filing in October.

The profit excludes $12.5 million in cash and 335,570 shares that Icahn is due to receive because the proposal was rejected. On July 9, he raised the offer from $36 and the company agreed to the payment in return.

Lear has added 36 percent this year, the third-largest gain among his holdings as of March 31. Temple-Inland, a maker of forestry products, which is splitting into three companies at Icahns urging, ranks first with a 42 percent increase. CSX, a U.S. railroad company, is second at 41 percent.

Icahns investment in Lear has been especially rewarding because of his timing. He bought 3.3 million shares last year at an average cost of $17.49 each, according to the October filing. The stock hit bottom at $15.60, a record low, in March 2006.

All told, Icahn accumulated 12 million shares at an average cost of $21.49. The rest of his stake resulted from an October agreement to purchase $200 million of stock directly from the company, a prelude to the takeover attempt.

Since the bid was made on Feb. 5, shares in makers of auto parts have climbed as the industry recovers from a spate of bankruptcies. A gauge of nine companies in Standard Poors benchmark U.S. indexes has gained 25 percent.

Lear essentially missed the rally because of Icahns bid.

The share price rose to $41.14 on the day after the deal was announced and slipped to a low of $35.40 on April 19.

Lear had been the cheapest of a dozen U.S.-traded auto-parts makers based on forecast earnings for next year, according to data compiled by Himanshu Patel, an analyst at JPMorgan Chase in New York. The stock traded at 11.4 times the firms projection.

“Value investors will now quickly take note of the stocks relative discount,” the analyst wrote in a report Tuesday. The result will be “a re-rating opportunity.”

Patel raised his rating to “overweight” from “neutral.” He was the first analyst to recommend buying the stock after Icahns failed bid, according to data compiled by Bloomberg.

Fourteen analysts have a “hold” rating or the equivalent and another says “sell.” Any shift in Patels direction may send Lears shares even higher and make Icahn even wealthier.

The firm, based in New York, has delivered a “positive surprise” of more than 10 percent for the last four quarters. No other member of the Amex Broker-Dealer Index, consisting of a dozen companies, has kept pace.

Merrill also had 10 percent-plus growth in earnings per share from continuing operations for the eighth quarter in a row. A.G. Edwards, the target of a takeover offer from Wachovia, leads the indexs members at nine straight quarters. Morgan Stanley is tied for second with Merrill.

The streak of profit increases may end this quarter at Merrill. Analysts are looking for earnings of $1.82 a share, down 9 percent from a year earlier.

Basell Holdingss $12.7 billion takeover offer for Lyondell, a U.S. chemical maker, is remarkably similar in value to the companys failed bid for Huntsman, also a U.S. chemical maker.

The $48 a share that Basell, a unit of billionaire Len Blavatniks Access Industries Holdings, agreed to pay for Lyondell equals 0.52 times sales. The comparable ratio for Huntsman, which the company lost to a higher bid from Apollo, was 0.5 times.

The offers were made at exactly the same multiple of book value, 3.74 times. The ratio shows how much Basell would pay for the companies assets minus liabilities.

Blavatnik signaled his interest in Lyondell two months ago by arranging an option to purchase an 8.3 percent stake through Merrill. Put that together with the comparisons, and it is clear why Basell did not raise its Huntsman offer to counter Apollo.

A MAN died yesterday when he was shot in the head and body outside a shop as students and lunchtime shoppers cowered in terror.

The victim, named locally as Jim McDonald, was gunned down outside a row of shops in Glasgow as he tried to flee the gunman.

The married father-of-two died on the busy street in the Cardonald area of the city.

Detectives immediately sealed off the area and began hunting the gunman who opened fire, just yards from the local Cardonald College.

Several students are understood to have witnessed the shooting and had to be comforted by members of staff.

Locals said the attack was part of a feud and said Mr McDonald, who was in his thirties, was killed as he tried to escape.

Neighbours claimed a gang burst into his home and chased him outside, before he was shot from a waiting car.

One man, who lives nearby, said: “He is from a tough family and has been in an ongoing feud with another family for some time. This is a tit-for-tat attack.

“Jim tried to run away down the hill, but a car pulled up and he was shot. Then the car drove away, did an about-turn to make sure he was dead and then drove away at speed.”

A woman neighbour added: “Jim was chased out of his house by some men, but there was someone else waiting outside for him. It is a bit scary because all of the children are just coming home from school and they are going to find out what has happened.

“I can’t believe it happened in broad daylight.”

The drama unfolded at 1:20pm yesterday outside the Corkerhill General Store, a licensed grocers and newsagent in Corkerhill Road.

The road was sealed off and residents were not allowed access for several hours while police and forensic teams combed the area for clues.

John MacDonald, 42, who lives nearby said: “I drove up and stopped outside the shops just minutes after it happened.

“I saw his body lying in the middle of the road. It was sickening and there was blood everywhere.”

Morag Nicolson, 58, said: “I heard two pops. I had never heard anything like it before and I thought at first it was a crash.

“It is terrible to have something like this happen so close to home.”

A spokesman for Strathclyde Police said: “Police were called to a shooting incident in Corkerhill Road, Cardonald, Glasgow. The man, who has still to be identified, died at the scene.

“Inquiries are at a very early stage and detectives are in the process of establishing the circumstances surrounding this incident.

“Any person who has not yet spoken to police and knows anything about this incident is asked to contact the CID at Govan Police Office on 0141 532 5436 or to telephone Crimestoppers hotline on 0800 555 111 where their anonymity can be maintained.