On the hot day of July 15, 1891, four women set off for the adventure of a lifetime in Boston Harbor. For nearly two weeks the quartet — well-educated, upper-class women from the Lowell area — “roughed it” in a quaint yet ramshackle cottage on remote Great Brewster Island, a place they considered “an enchanted isle.”

The women kept a meticulous diary of what they did, ate, read, and discussed during the sojourn, dubbed “Ye Square Partie of Ye Merrie Trippers.” That diary, now a prized addition to the collection of the Schlesinger Library of the Radcliffe Institute for Advanced Study, offers an unusual perspective into the daily lives of 19th century women, leisure habits of the era, and the history of Great Brewster, which today is part of the Boston Harbor Islands national park area.

With its 58 pages of text, photographs, and watercolor illustrations, the diary opens a window into another place and time, as well as being an appealing account of an “excellent summer adventure,” said Kathryn Jacob, the curator of manuscripts at the Schlesinger Library.

“If one ‘reads’ the text and the images carefully, this beautiful diary tells us a great deal about Great Brewster Island, about this group of women and the friendship among them, their strengths, their sense of humor, as well as a great deal about class, leisure, food, use of space, and photography, among many other topics,” Jacob said. “There is a great deal of scholarly interest in women and the natural environment, to which this volume speaks.”

Yet the record of this excellent adventure might have been lost except for Harvard Professor John R. Stilgoe’s love of old books.

“I have never been able to pass a secondhand bookstore,” said Stilgoe, the Robert and Lois Orchard Professor in the History of Landscape. He discovered the diary by accident when he took a break from a bike ride to browse a used bookstore on Cape Ann. Stilgoe instantly knew it was a treasure that Harvard should purchase and keep whole. But after he alerted the Schlesinger Library, the library staff found that the diary had been sold to a dealer who apparently was considering cutting it up to sell its illustrations individually. However, the library was able to obtain the manuscript in 1999.

The diary’s visual images and emotional honesty are “everything that guides my teaching and my research,” said Stilgoe, whose work examines North American landscapes, seacoasts, and environments. Certainly the women were “special”; they were obviously educated, well-read, and wealthy enough to have acquired photography and art skills. “But I think the diary really indicates how competent they were,” he said. “That’s what comes through. It’s an incredible document of competence.”

It has captivated scholars like Jacob and Anne Engelhart, the head of collections services at the Schlesinger, who both marvel at the women’s camaraderie and the author’s self-awareness.

Evidence shows that the primary author was Helen Augusta Whittier (1846-1925), daughter of Moses and Lucinda (Blood) Whittier of Lowell. Helen Whittier was an art teacher, a photographer, an avid promoter of women’s clubs, and an entrepreneur who helped run her family’s mill business in Lowell. The identities of her companions are obscure, although at least some were members of the XV Club, a Lowell literary women’s club founded in 1860.

The diary begins on July 15, 1891, when the four women debark from Pemberton Pier in Hull on the sailboat of “William the Swedish fisherman” who lived on Great Brewster. Whittier never mentions her own name or that of her comrades; she refers only to the “Autocrat,” the “gentle Aristocrat,” the “artistic Acrobat,” and the “veracious Scribe.” Shedding identities was apparently part of the adventure.

After setting up housekeeping, the women spent their time reading, sketching, taking photos, gathering wood, and engaging in spirited discussions — all chronicled by the “veracious Scribe.” At night they read out loud to each other and played cards and Halma, a board game.

As one entry reads: “After dinner instead of our usual walk, we sat on the piazza [deck] and enjoyed the beautiful sunset which filled the sky and water with glory and when the moon almost at the full appeared from behind the … clouds we felt that Nature had shown us many of her varying moods on this day. We sat in the moonlight until late discoursing as old friends will, then betook us to the dinning room to read aloud a Sermon on Faithfulness and then a half hour of Kenilworth [likely the novel by Sir Walter Scott] finished our day.”

The Merrie Trippers reveled in their casual island attire even though photographs show them in long skirts and hats that to modern eyes look formal enough for the office. They hunted clams – not always successfully: “After dinner the Aristocrat and Autocrat with much preparation of rubbers, old skirts, pails and spoons, went forth to dig clams for food tomorrow. The Scribe and Acrobat were left to wash dishes, then to meet the other party at the northern end of the isle, to assist in bringing home the clams. With regret, they left a ruddy sunset and soon found their friends with light pails, cut hands and long faces, but no clams.”

But like any modern Girls Night Out, the women didn’t stint on eating. The Scribe carefully noted the cuisine for each meal. On July 27, for example: “Breakfast – minced tongue and potato, buttered toast, oatmeal, tea — Lunch – crackers, cheese, olives, gingersnaps, milk — Dinner – beef stew, tomato sauce, cake, chocolate.”

This careful attention to food, Stilgoe speculated, may indicate the women supervised home staffs. “They were on vacation not only from their families but from their servants,” he said.

Still, the women frequently had visitors, who brought supplies like bread and tomatoes. The keeper of the Boston Light lighthouse sailed over from Little Brewster Island for a chat, and residents from nearby Calf Island dropped by with letters and the Boston Sunday Globe. Members of the XV Club even managed to send chocolates. “They talk about going to an isolated island, but it was a very social place,” Jacob noted.

Finally, on July 31, the women boarded William’s sailboat for the return home: “At 10:30 a.m. we said goodbye to our enchanted isle, so difficult to reach, so hard to leave.” The Scribe added, sadly: “We leave behind us the uneventful, idyllic days, like no others in our lives, with their placid serenity, their pleasant spice of labor, the unruffled happiness of accustomed comradeship and all the glory of sea and sky….”

Whittier, who never married, stayed active until late in life, particularly in women’s clubs. She took over the Whittier Mill in Lowell on the death of her father and his only son, and oversaw the building of a second mill in Atlanta. “Miss Whittier, with her gentle, quiet ways and wonderful business ability, is a fine example of what the true American business woman may become,” noted the 1897 book “Occupations for Women,” by Frances Elizabeth Willard.

Whittier’s island trip likely remained a high point in her life. A March 25, 1906, Boston Globe story about the history of the XV Club of Lowell refers to the “memorable” sojourn on Great Brewster when club members “successfully undertook cooperative housekeeping, though so many ‘miles from a lemon.’” After her death in 1925, Whittier’s diary was passed to a friend who passed it to her son; Stilgoe is unsure precisely how it ended up in the bookstore.

But it remains the only record of a special moment in time. Today, all traces of the Merrie Trippers’ beloved cottage on Great Brewster have disappeared.

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