HEN FRIGATES: WIVES OF MERCHANT CAPTAINS UNDER SAIL, by Joan Druett, Simon & Schuster, 274 pages, hardcover, $25.

From our late 20th century vantage point, it’s tempting to think of married life at sea in the Age of Sail as romantic. Off to see the world with your beloved. Sailing into the sunset together.

Well, as the saying goes, if you want the real story, ask someone who has been there.

In a sense, that’s what marine historian Joan Druett has done in “Hen Frigates: Wives of Merchant Captains Under Sail.” From the letters and diaries of women who took to the sea with their husbands, and from voluminous supporting research, she has drawn a vivid composite first-person account of life as wife and mother on merchant ships in the 1800s and early 1900s. She provides glimpses, as if through a porthole, of feminine life aboard vessels ranging from small family-operated coastal cargo vessels (the “trucks” of the era) to glamorous and speedy trans-Atlantic packets; whaling ships whose voyages lasted for years; and the aristocratic blue-water clippers who raced each other while hauling precious cargoes halfway around the world.

The women who speak through Druett’s book tell us that the realities of life aboard most sailing ships in the days before refrigeration, radio communication, modern navigational aids or the invention of the marine toilet were far from romantic. Cramped quarters, a restricted diet, almost undrinkable “fresh” water, and the ever present possibility of storms and shipwreck were standard. Most seagoing women chose to live with danger and discomfort only because the alternative was worse: A busy sailing captain might spend only days or weeks at home in the course of a year, leaving his wife on her own the rest of the time.

Happiest in domestic life afloat were the “sister sailors” (as seagoing wives termed themselves) such as Georgia Maria Gilkey of Searsport. Georgia, who grew up in a seafaring family herself, doubtless knew what to expect when she married Capt. Phineas Banning Blanchard of the 1,700-ton square-rigger Bangalore in 1906, and they set off on their honeymoon voyage around Cape Horn. For some women who were new to the sea, the first voyage was enough for a lifetime: When Henrietta Elliott became the second Mrs. Joshua Slocum, her first journey by sea with her famous sailor husband and his two sons from his earlier marriage ended in shipwreck on the coast of Brazil. Once the family was safely home in New York — reached by a boat that the resourceful Slocum built himself, Henrietta never sailed again.

Sailing wives had a vast new world to learn. It embraced everything from the shipboard hierarchy of officers and seamen to the timekeeping system of bells that dictated the rhythms of life at sea. Wives also played a practical role: On packet schooners, which sometimes sailed a thin line between safety and speed in their efforts to adhere to a schedule undeterred by weather (a novel maritime policy in the mid-19th century), captains’ wives functioned as hostesses to help entertain bored, and sometimes seasick, passengers who paid as much as $200 for the trip.

Wives also learned to navigate — for good reason. The captain was often the only other person on board with this essential skill, and more than one “sister sailor” became responsible for keeping the ship on course when her husband was incapacitated or dead.

For seagoing wives, setting sail with their soulmates also meant setting off with a first mate, second mate and other crew members. Privacy was sometimes harder to come by than piracy, especially on smaller ships. Reaching port did not mean more time for married bliss; the captain was likely to be occupied ashore with ship’s business, which sometimes included looking for a paying cargo to replace the one he was unloading.

Conventions surrounding women’s role in the Edwardian and Victorian eras from which most of Druett’s sources are drawn — not to mention the encumbrances of women’s clothing in an age when skirts swept the floor — confined most sister sailors to typical feminine pastimes such as sewing. (Mary Stark, whose husband captained the clipper B.F. Hoxie, worked elaborate scrimshaw patterns on a whalebone corset during the long trip home from Honolulu with a cargo of whale oil.)

As Druett’s account makes poignantly clear, women stayed (or were kept) out of the seagoing limelight even when circumstances pushed responsibility on them. Jennie Parker Morse took over command of the John W. Marr when her husband, Capt. George W. Morse of Bath, died off Madagascar in 1881. She preserved her husband’s body in spirits (a standard seagoing embalming practice of the time), suppressed a mutiny, and got the ship safely back to New York. According to Druett, contemporary newspaper stories reported only the ship’s’ return and its captain’s death, with no mention of Mrs. Morse’s part in the drama.

The birth of children at sea was an inevitable consequence of wives aboard, and the challenges of raising a family on a sailing ship provide some of the most interesting (and occasionally harrowing) detail in this book. Small babies — usually delivered by the captain — were sometimes sewn into their cradles to keep them safe. With disposables a century away, and fresh water in chronically short supply, diapers were an almost insoluble problem. Toddlers who learned to walk on pitching decks were in danger of falling down companionways or through open hatchways.

The unavailability of medical care made even common childhood illnesses and injuries life-threatening. Surprising numbers of children seem to have survived this strenuous upbringing; Druett cites one source as saying that 70 residents of Searsport were born at sea.

“Hen Frigates” will introduce you to women so fascinating that you may wish Druett had spent more time with some. We long for a more complete account of the flamboyant Maine captain James “Shotgun” Murphy and his wife, Maria, who sailed with him for 35 years and raised their family aboard. Conversely, some stories are no less affecting for their brevity. The gulf of a century and a half can’t blunt the pain we feel for Capt. Elisha Sears of the Wild Ranger when his pregnant 20-year-old wife Bethia dies. “Why has she been taken from me — oh, God have mercy,” he writes in the journal Bethia had been keeping for the entertainment of her sisters at home.

Sailors will particularly enjoy this book, as will those familiar with the coastal Maine communities which were home port for Druett’s sources. Her bibliography will be valuable for anyone wanting to look further into this little-explored area of marine — and feminist — history. But as a journey back in time and a detailed introduction to another world, this book stands on its own as a solid and entertaining volume.