"I hope they don't steal this," said Canadian Ambassador Allan Gotlieb, balancing a freshly lit Monte Cristo on the edge of a marble bench in the old Federal Reserve Board Building lobby. "They don't get Havana cigars around here very often."

The Fed doesn't get shows as memorable as "The Prints of James Jacques Joseph Tissot"(1836-1907) very often, either. This one, just opened, is on loan from Gotlieb's collection of Tissot prints--said to be the finest in private hands.

"What I find so appealing is the sense of timelessness that comes with those long Victorian afternoons--the languidity, the richly textured light," said the former Rhodes scholar and international law expert, glancing over the show.

"That's Kathleen Newton, Tissot's mistress, whom he met when he left Paris to live in London in 1876. There she is on the lawn with members of her family. And that's Tissot's garden in St. John's Wood. It figures prominently in his work."

So does Mrs. Newton, who pervades these scenes of fashionable London--elegant ladies swathed in high-Victorian millinery, shaded by parasols, picnicking in boats on the Thames, watching croquet, lolling about on wicker chaise longues. Newton, who died of consumption at age 28, is also the obsessive subject of several portraits, her face sometimes wan and beautiful, but more often vapid and too, too sweet.

It is a problem Gotlieb recognizes. "When we look at her today," he writes in his incisive catalog essay, "we must admit that cold as she looks at times, remote as she seems, and even superficial, she draws us to her in some undefinable way."

It's true. There is an otherworldliness, a psychological tension, in her gaze, and in the gaze of all his women, that makes one forgive the often cloying illustrational quality of their faces.

An idiosyncratic French painter, nearly forgotten until his current revival, Tissot worked in London and Paris during the Second Empire, and--like his friends Degas, Manet and Whistler--was caught up in the etching craze of the 1860s. The show includes 53 of the 70 etchings, dry-points and mezzotints he made in his lifetime.

Though a great financial success, Tissot took a beating before and after his death, not only for his persistent academic realism, but also for the fact that half the images he etched between 1875 and 1886 were reproductions of his own paintings--not to mention the compositional ideas he'd filched from others--including Whistler, Manet and Japanese printmakers.

Henry James, in a 1877 review, was most unkind. He called Tissot's style "hard," his humor "trivial" and his sentiment "stale and disagreeable." Until recently posterity sided with James; the case was clinched when Tissot returned to France after Newton's death and spent the rest of his life making high-minded illustrations of biblical themes. He was virtually forgotten until a decade ago.

Gotlieb began collecting prints in the '50s when he was at Oxford, though it was 10 years after his first purchase--a Daumier--that he saw and bought his first Tissot etching, titled "Summer Evening," in a London gallery. "I paid $200--more than I should have," said the man Pierre Trudeau picked to organize the Ottawa Summit Economic Conference in 1981.

But he soon made up for it.

"I was lucky. In Paris, by sheer chance, I found the man whose grandfather had published Tissot's prints. I bought 30 of them--at an average price of $30."

He's been collecting them ever since, though the market has now changed dramatically. Gotlieb's most recent acquisition--the very print Henry James had panned, "The Gallery of HMS Calcutta"--cost him $3,000 at auction. He now owns 130 Tissot prints, including many different states and proofs. It's the most complete collection, he said, outside the Bibliothe que Nationale. Forty hang in the Canadian Embassy dining room.

There's a distinct stylistic shift in Tissot's work from the airy, light early scenes, such as "Lover's Quarrel," to the claustrophobic, friezelike images from his late series based on Parisian women. Gotlieb reads these as "static and unreal," but sees them as precursors of his beloved art nouveau, which he also collects. Despite such shortcomings in Tissot, he has no doubt that the artist deserves better regard than he has had. Those who look carefully at this show are bound to agree. There is an element of psychodrama in his work--an emotional undertow that keeps you looking far longer than you would have expected at first glance.

"He was dead as an artist for 60 or 70 years," said Gotlieb, obviously savoring his contribution to the renewal of interest in Tissot. "There was a sort of condescending revival--along with other artistes--quaint. Today his oils have gone entirely out of reach, and there is the recognition that he was not a conventional artist."

Gotlieb had resumed liaison with his cigar when Preston Martin, the new vice chairman of the Federal Reserve, stopped to say "thank you" for the loan of the show, and that he always went out of his way to see the art when walking through the building.

"Glad to hear it," said Gotlieb with a chuckle. "I hope it makes for better monetary policy." He added hastily, "I mean, it's great now--but even better. Ah, well, it was just a joke, just a joke."

The vicissitudes of monetary policy notwithstanding, the show will continue at the Fed through March 9 in the old Federal Reserve Board Building on C Street between 20th and 21st streets NW. The show is open to the public only on Wednesdays, Thursdays and Fridays from 11 a.m. to 1 p.m. or by appointment (call 452-3686). Beyond the Single Frame

Back in the 1880s, Eadweard Muybridge used sequential photography to examine animal and human locomotion.

More recently, photographers have been using it to move beyond the esthetic limitations of the single frame. Within this trend Jan Groover, Duane Michals and Eve Sonneman are well-known practitioners. "Sequential Photography," a small, provocative show at the Gatehouse Gallery of Mount Vernon College, introduces seven lesser-knowns. The results are varied and interesting.

Californian Lisa Bloomfield, in her "Beach Narrative," uses 16 separate photographs with short sentences penned below to convey the sense of a mating dance between a man and a woman who toy with seaweed and look for shells.

The challenge in such work, as opposed to the journalistic photo essay, is to balance the obvious and the obscure. Mark Power's portraits of two nubile girls, matted with photographs of massed potted plants, seems a too-obvious reference to fertility. More balanced are Jay Boersma's small, horizontal images showing people in cars and roadside diners, the cut-and-reassembled photographs speaking simply yet eloquently of human isolation.

But it is Michel Krzyzanowski, a Dutch photojournalist, who delivers the highest form of poetry here in minimal/conceptual studies such as a sequence of handprints in the sand.

Organized by Washington photographer Gail Rebhan, the show continues at 2100 Foxhall Rd. NW (enter on W Street) through Jan. 28. Hours are 10 to 5 daily.