The Brown family found the Schweppes bottle on Wharton Beach near Esperance, Western Australia, during a beach cleanup on October 9. Inside were pencil letters from Privates Malcolm Neville, 27, and William Harley, 37, dated August 15, 1916.

Their troop ship, HMAT A70 Ballarat, had left Adelaide three days earlier, bound for the Western Front. Neville was killed in action a year later; Harley survived the war but died in 1934 from cancer his family believed came from being gassed in the trenches.

Neville asked the finder to deliver his note to his mother in Wilkawatt, South Australia. Harley, whose mother was dead, said the finder could keep his. “May the finder be as well as we are,” he wrote. Neville told his mother he was “having a real good time,” adding, “The ship is heaving and rolling, but we are as happy as Larry.”

Deb Brown believes the bottle remained buried in sand dunes for over a century before coastal erosion exposed it. Despite being wet, the writing was legible, allowing her to contact both soldiers’ families.