This novel is as much about the sinking of the Titanic as it is about dressmaking. Written by D.C. journalist Patricia O’Brien under the pen name Kate Alcott, it’s an unashamed girlie-book with a woman’s attractive behind adorning the cover, sporting an elegant semi-bustle. The dress seems to bunch up under the arms, and you can spend several minutes figuring out how someone put the thing together. Which brings up an interesting aspect of “making history,” particularly the kind that Virginia Woolf used to talk about: the flocks of girls with bits of sewing in their laps, chattering about men, defining them, often by bursts of rude laughter. That’s a form of history, too.

“The Dressmaker” has all the required girlie-tropes. All the young girls worth knowing wear their hair carelessly unpinned; I suppose it shows their willingness to cut loose and party down, no matter what the century. Their love interests have blue eyes and unkempt beards. The young protagonist, Tess, notices a handsome young sailor: “His hair was unruly, but swept aside with careless confidence,” and his eyes were “indeed as blue as the sea.”

The better groomed the characters, the more morally dubious they are. We’re talking about the Titanic, remember, and how it perished after hitting an iceberg on its maiden voyage. A number of rich people are traveling on this behemoth, including Sir Cosmo Duff Gordon and his wife, Lucile. She’s the most famous dress designer in the world, but some upstart named Chanel is out there snipping her scissors with murderous intent. Lucile is still trapped in overly elegant gowns made of satin and chiffon, each one graced with a dreamy and pretentious name such as “Sighing Sound of Lips Unsatisfied” or “Frenzied Song of Amorous Things.”

It just so happens that the girl named Tess (with unkempt hair and plenty of ambition) accosts Lady Duff Gordon on the pier of the Titanic and begs to come along. After a pro forma argument, Lucile agrees to hire her. (Her own lady’s maid has failed to turn up.) Lucile has Tess moved into a stateroom next to her own, and she is able to wander the deck — and some of the sumptuous public rooms where she meets a mysterious millionaire who promptly falls in love with her and wants to give her the whole world. He’s been divorced twice, but he’s handsome, charming and altruistic.

The reader may be forgiven a little depression at this point, contemplating the sinking of the Titanic that must come next, but the author dispatches with that in a dozen pages or so, and the real story begins.

Tess is lucky enough to get in a lifeboat, on which she — along with the Unsinkable Molly Brown — makes good use of the oars. Lucile and her husband have escaped in another boat, from which it turns out they have pushed off non-swimming unfortunates. There’s also another couple — with a husband who has escaped by draping himself in a tablecloth and pretending to be a woman. Once the survivors are safely on land, tears and recriminations ensue. The American public is not in a forgiving mood.

The last third of “The Dressmaker” relies heavily on genuine transcripts from government hearings, and we learn a good deal about what it was like when the ship went down. But we also follow Tess as she learns about the high-fashion business in New York. The dresses are exquisite, but technology is changing everything. Zippers are coming on strong, and the art of handmade button holes is going down the drain. Zelda Fitzgerald and the advent of “sportswear” is just around the corner. The whole world is changing. Tess will have to find a suitable career, and, of course, she gets to choose between the gentle, intelligent millionaire and the boy with the careless hair and those sea-blue eyes.

There’s something a little bit faulty about the American Dream, especially as it pertains to beautiful young women. There aren’t enough rich men to go around. So we’ve been trained to ignore those darling boys in yellow convertibles, even in our escape literature, and go for the poor but honest men with unkempt hair, never minding how un-cute they’re going to be when their hairline recedes and they start drinking a gallon of beer a night. True love comes in many packages, but those guys with millions of dollars and a ready wit are going to be out of our league. Even in a girlie fairy tale.

See regularly reviews books for The Post.

The dressmaker

By Kate Alcott

Doubleday, 306 pp. $25.95