Unless you are an avid sailor, the name Joshua Slocum conjures up, if anything, only a vague story of sailing solo around the world and being lost at sea. In his latest book, Stan Grayson easily convinces the reader that there is much more of interest to the story.

Slocum’s life was extraordinary: a hardscrabble ascent from a failed Nova Scotia farm to hobnobbing with presidents; advancement from the lowly forecastle, “through the hawsehole,” to world-famous ship’s master; finding true love and then true grief; and finally, a heart-rending decline and fall. As far as is positively known, Slocum was last seen departing for a winter sail to the Caribbean. He never returned.

Grayson started “picking at the corners” of the story in the mid-1970s. He was very conscious that someone had written what he generously calls a “pioneering biography” 20 years before. Was there anything more to be said about the great seaman?

He kept picking away until he had enough new material for a magazine article. But still he couldn’t let go, and the “ever-widening reach of the Internet” fed his habit. The final bonus was a cornucopia of information bequeathed to him by a Slocum relative. The result is “A Man for All Oceans,” a riveting book.

The Slocum legend was assiduously promoted by the man himself in “Sailing Alone Around the World,” and Grayson is judicious in his assessment of the inevitable differences (to use a neutral noun) between saga and evidence. He starts from the premise that, where Slocum “concocted, rearranged, or even lied about key events” of his life, he had good, though not necessarily obvious, reasons. By trying to unravel them, the historian can “gain insight into Slocum’s motives, feelings and actions” but must “tread carefully,” Grayson writes. We can never know for sure, just as we will never know exactly what befell Slocum at the end. By placing the known facts of Slocum’s life in the fascinating milieu of a sailing tradition struggling to survive, “A Man for All Oceans” gives a powerful evocation of both.

At the time, 1895, no one thought a man could sail alone around the world, least of all in a 40-foot boat. The voyage lasted more than three years, and Grayson gives a vivid account (Slocum kept an immaculate log and wrote letters from the ports that he stopped at), accompanied by splendid maps. The most telling one shows how, having threaded the Straits of Magellan, a gale forced the Spray south toward Cape Horn until Slocum had to do it all over again. It was also here that he used metal tacks spread over the deck to warn him of, and ward off, a deadly boarding by the native Fuegians.

However, there is a tremendous amount fore and aft of the circumnavigation. Another map shows the numerous voyages all over the globe Slocum made on various boats, always accompanied by his wife, Virginia, and his growing family. Few of these cruises lacked for drama. On more than one occasion, Slocum had to use his “big fist” to get his way or restore order, and once he had to shoot his way out of a mutiny. After his ship was wrecked off Montevideo, Slocum built a new vessel to transport his family home. On another occasion, he commanded an ironclad torpedo boat sent by the US government to bolster a Brazilian dictator. Designed for coastal defense by the creator of the Monitor (of Merrimac fame), it had to be towed to Brazil and nearly sank; the rebellion was over before they arrived.

Slocum never recovered from the death of his beloved first wife. Getting away from his memories was probably one of the impulses behind his solo voyage. After that achievement, despite success and fame, he and his boat slowly fell apart. Grayson suggests dementia may have played a role, but a touching reminiscence attests that once under sail, Slocum was every inch a captain to the end.

The book is profusely illustrated, although I wish the painting of skipper and his boat by Charles Gifford had been incorporated at a decent size between the covers, instead of being relegated to a thumbnail on the back jacket; I’m sure the author would agree. For the serious sailor, there are appendices aplenty on the Spray’s lines and sail plans.

“What a tale it is!” Stan Grayson exclaims about Joshua Slocum’s life, and he has made the most of it. I’ll bet “A Man for All Oceans” will be spotted all over Maine’s beaches and harbors this summer. At least, it should be.

Thomas Urquhart is a former director of Maine Audubon and the author of “For the Beauty of the Earth.”