Every night on television the pictures are beamed into British homes: Argentines screaming, crying, chanting, or beating their chests over their right to the Falkland Islands.

The contrast in Britain is striking, despite the likelihood of an escalation of warfare and bloodshed.

So far, just two small public demonstrations have taken place here over the islands that Argentina seized almost seven weeks ago. Both were opposed to Prime Minister Margaret Thatcher's policy of retaking the Falklands by force if necessary.

"The islands are so close to Argentina and they are 8,000 miles from Britain," said Bill Hayward, a shipping agent, as he sipped his bitter in a West End pub and tried to explain the phlegmatic British attitude.

Many Britons acknowledge that they knew little or nothing about the islands until the crisis. One, confusing them with the Shetland Islands, said he thought they were off the Scottish coast.

Some say their main acquaintance with the Falklands was through the weather reports that included the islands because of their navigational significance to this nation with a long maritime history.

A bartender said that although his patrons talked about the Falklands, interest was not nearly as keen as that shown by the media, where it is hard to find any other news.

"All that could change if there is a lot of bloodshed," Hayward said.

THERE WAS NO feeling of imminent warfare at the opening today of the tradition-laden Chelsea Flower Show, the showcase of Britain's love affair with gardening. Thousands paid more than $10 apiece for the right to ogle the fragrant displays and plan their summer gardens.

The Falklands were literally 8,000 miles away, despite all the expectations that Thursday might be D-Day of some sort.

"Everybody is spending money like it is going out of style," said John Mattoch, an Oxford rose merchant who has been displaying for 25 of the 61 shows.

With a stretch of the imagination, the names of Mattoch's blood-red roses, Lili Marlene and Intrigue, could evoke some wartime memories.

In fact, Mattoch's dozens of varieties of roses, which had the honor the central display in the show, surrounded an obelisk memorializing a war long forgotten.

The monument, at the center of the Chelsea Hospital gardens, was established to "the memory of 255 officers, noncommissioned officers and privates of the 24th regiment who fell at Chilianwalle" Jan. 13, 1849.

Chilianwalle was one of numerous battles in a war in India, one of many conflagrations this nation has been involved in. Even in Britain, few people would recall the war; few of the flower-lovers even noticed the monument.

"Just like Chilianwalle, the Falkland Islands war will be very obscure 10 years from now," Mattoch said.

More in keeping with the mood of the show were two new roses for the season, Iced Ginger and Just Joey. A passer-by looked at the perfect golden petals of Just Joey and murmured, entranced, "Just georgeous."

OUTSIDE THE SHOW, however, the aura of war crept in. A woman collecting for the Army Benevolent Fund, a charity for veterans, said contributions were up because of the Falklands.

Back at the Marlborough Head pub in the West End, barmaid Liz Knox said most of her customers talked about the Falklands dispute, but with little emotion or disagreement.

A teen-ager who declined to give his name said there would be more feeling if Britain had conscription rather than a professional army. Asked what he would do if the draft were resumed and he conscripted, he said, "I'd be scared, but I'd go."

He also predicted that emotions would rise if the three British teams in next month's World Cup soccer tournament in Spain pulled out because of the presence of the defending champion, Argentina.

If anything, most people seem to be impatient with the efforts to reach a peaceful settlement.

"They all seem to be supporting Maggie," Knox said, but many people maintain that "she should get on with it."

"The feeling is that the islands are not worth killing people over, but we have a right to go in and take them back," Knox said. In fact, it is difficult to find Britons who do not support Thatcher in her attitude of standing up to aggression.

At a recent dinner party in an upper middle-class neighborhood, a film maker's wife said, "We must defend this principle. We're only doing what is right and necessary."

A physicians's wife responded with frustration, "There must have been some way to avoid it. I think it's horrible."

THERE IS LITTLE reflection in London of the jingoism of the extremist newspapers such as the largest-selling tabloid, The Sun, whose daily headline across pages two and three says: "The paper that supports our boys."

The Sun has made a major concession to the hostilities. It has moved far back into the paper its daily picture of a topless beauty who usually adorns page three.

British irony and cynicism have been reflected in the Falklands crisis.

A recent pro-Irish parade was punctuated with chants of "self-determination for the Irish people."

Splinter groups calling for liberation for Namibia and freedom for Iranian Fedayeen guerrillas found their way into the parade, but there was no reference to the Falklands despite Thatcher's emphasis on the islanders' need to exercise their own right of self-determination.

A cynic recently commented on the fact that the Royal Navy task force now has 12 men for each of the 1,800 Falklanders and the government has spent at least $275,000 per islander so far to regain them their rights.

Noting that Britain has always had strange measures, including 14 pounds to the stone, he said: "Perhaps we should have a new word standing for 1,800. We could call it a falk."