IT IS 5:30 P.M. and a slight rain is falling in the north quadrant of the United States Military Academy. The fog from the Hudson River has rolled in over the campus and the great mass of uniformly gray buildings that are West Point has become indistinguishable from the atmosphere. In the courtyard, a brigade of cadets--dressed in gray rain slickers, gray caps with gray rain hoods, and gray trousers--lines up for formation and review. It looks somber and depressing, one first class cadet (senior) says, but look on the bright side. Things get even worse during January and February (they call it the "period of gloom" at the Point) and everything--the grass, the water, the faces of 4000-plus cadets--turns gray.

Since 1802--when Congress established the academy to train officers for the army--officers-to-be have passed through the halls of what one historian has called this "citadel of sense and stability." Although things at West Point look much the same as they have for decades, much has changed since Douglas W. MacArthur led his class of cadets through the Long Gray Line. No longer can upperclassmen harass plebes throughout meals so they don't get a chance to eat; no longer must plebes be able to spout back on command how many lights there are in Cullen Hall (340); no longer is "silencing" permitted--a form of extreme ostracism and abuse inflicted on those found guilty by their peers of breaking the honor code but absolved by a higher authority.

The academy has seen women march through graduation and has posted a Black as the first captain of cadets (akin to student body president). Plebes now substitute "Hare Krishna, sir" and "No nukes, sir" for the more traditional campus greetings. Male cadets, who once paraded naked through barrack halls, are now required to wear bathrobes when they go back and forth to the shower.

But West Point fancies itself a timeless institution and, as graduate Dwight D. Eisenhower remarked on his return to the campus, "Some things never change." On Saturdays, two regiments parade in full dress on the great expanse of the Plain. At morning inspection, a cadet's "tac" (tactical officer) can slap three demerits on him for "messy drawers." Cadets must arrange their books on their shelves in order, from tallest to shortest. Physical education is a graded course and each year a cadet is required to run the obstacle course. They call it the O.C. in public, "the suck" in private: cadets must do a belly crawl for 20 feet, jump a gymnastic horse, climb one wall, do the monkey bars, go feet first through a tire, do the parallel bars, leap another wall, take more monkey bars, climb a rope, carry a medicine ball around a 1/12 of a mile track, do the same with a baton and run a final half-lap. All in three minutes and 41 seconds. If you don't pass, you do it again.

AT THE BASE of this school for soldiers is the fourth class system, a social system which allows a first class cadet to stop a plebe headed for bed at 1 a.m. and demand that he "talk" because he's heard the freshman is Australian and has an interesting accent. It starts on day one--"R" day they call it at the Point--when the new cadets come in at 8 a.m. and by 5 p.m. are shorn, supplied and marching in military formation.

The next two months, when plebes are put through basic training or "Beast Barracks," are a cadet's introduction to the system. "We take people who are just like you," one senior explains as 4000 identically dressed people eat cold pizza in the world's largest dining hall, "and in six weeks, we teach them to be one of us." It's like an initiation into a fraternity, explains another, "a big fraternity." "The new cadet's waking hours are completely controlled," reads the plebe's bible, or Bugle Notes. "They don't have time to think," one cadet explains. "We want it that way."

The system is designed to socialize cadets, to strip them of their civilian values as it strips them of their civilian clothes. In a required course on leadership--the cadets call it "Leadersleep"--an instructor is trying to urge first classmen to try and determine what individual characteristics separate leaders from other people. "Individual traits, sir?" questions one cadet who looks as if he has rubbed his black shoes with Formula 409 for 15 minutes. "They issue them to you on the first day of 'Beast,' sir."

Two-thirds of the cadets who seek psychiatric help during their four years on the Hudson do so doing the first two months. The constant pressure to perform--a main feature of one's years at the Point--is intense. Pressure means anxiety and anxiety means constipation. "When I first came here," one senior can admit laughingly now, "I didn't shit for a week." Then he frowns. "I know of one girl who didn't have her period for three months."

'Beast' is only the beginning of a year that many cadets say they'd like to forget. Army brat Bill Fullerton went to Vanderbilt for a year and a half but found himself drifting and dropped out. He sold Kirby vacuum cleaners for six months before coming to the Point. "There wasn't a day that went by for the first year that I didn't think about leaving."

Although the harshest plebe requirements have been dropped, some traditions remain. Plebes must take turns standing in the barrack halls and yelling out the dress for the day and the minutes remaining until formation. It is easy to recognize them; they are not supposed to initiate conversations and they must walk 120 steps a minute, always sticking to the walls of the stairwells and greeting upperclassmen. If another cadet wants to know what's happened in Iran yesterday, the plebe must answer. He is required to read and know the news on the front page of The New York Times and the cover of the sports section. "One of the strategies for getting through plebe year is sleeping whenever you can," says a cadet. "That way you exist for less time."

Even with its irrationalities, cadets say that the fourth class system is important because it separates West Point from other colleges. "Beast" is necessary, they say, for it helps them to adapt to a military environment--something they function within for at least five years following graduation. People who come to West Point in search of the "free education"--cadets actually receive half a second lieutenant's pay during their four years--don't usually stay around. The attrition rate hovers at 25 per cent. "No one comes just for the education," says one cadet who wants to be an army officer. "If they do, they either quit--or are quitted." The message from other cadets is the same: "You either accept the system or go home."

FOR THOSE who adapt, each year brings increased privileges and freedom from the reams of rules and regulations. Following classes and duties on Saturday, seniors are allowed to take weekends off. They are also allowed to drink at the First Class Club, keep their cars at the academy, and skip certain meals. Those with special responsibilities are excused from formations and parade duties. And, as the time passes, as with any college, they learn how to beat the system. Cadets sleep in their "green girls" (army comforters) so they don't have to make their beds every day.

But the vast majority of rules are still enforced and the list of taboos is long. Each class is given a demerit ceiling for each month; going over the linit earns a cadet several hours of "walking the area," a practice of being forced to dress in formal uniform, mount rifle upon shoulder and walk back and forth in the courtyard. If you skip a class, you automatically "walk."

Breaking rules which tread what one cadet calls "the fine gray line" between the "honor code" and regulations brings harsher punishments. Last year, Fullerton was caught drinking wine in his room and was slapped with 30 hours of "walking" in return. It would have taken months to work it off, he says, but under a little-know academy rule which states that a visiting head of state can grant amnesty for "walking" cadets, a stopover by the Queen of Thailand cut it short.

There is an underground of sorts at West Point--cadets who do the minimum and try constantly to skirt the rules--but they are clearly in the minority. Some people break the rules against drug use, but for most, it isn't worth the consequences of resigning your commission and leaving the academy. "Drugs are a death warrant here," one officer explains. "You might as well pack your bags."