My grandfather, a cultured and sensitive man, rarely let on how deeply the Western Front haunted him. As his years stretched towards the end, the old fellow occasionally confided a story of his time on the Somme and Bullecourt and Pozieres and other ghastly places that carved too much from his youth and left shrapnel in his body and nightmares in his mind.
Passchendaele left him with a lifetime horror of mud. He told me just once of an experience there.
Passchendaele is a place in Belgium where torrential rain and artillery bombardment in 1917 reduced a soldier's world to a near-unbearable slog through sucking ooze and flooded shell holes that swallowed men and horses and mules.
My grandfather had managed to gain the relative stability of a duckboard - a pathway of wooden slats laid over the mud - when he heard through the mist a voice. "Hilfe, hilfe." It was a young German soldier crying for help. The boy was flailing in the soup of a shell hole.
Here were two young men on the opposite sides of a war suddenly locked in something more hideous and immediate than the knowledge that minutes before, they would willingly have shot or plunged a bayonet into the chest of the other. This was altogether more elemental and pitiable than the fury of battle.
My grandfather stretched out and offered the barrel of his rifle to the drowning German, proffering the weapon as salvation, urging him to take it. The boy in his panic couldn't reach it. He slipped beneath the mud, leaving only a memory frozen in the mind of a young Australian who couldn't shake it all the years of his life.
Passchendaele was a ridge and a village a few miles from the Belgian city of Ypres, known to the soldiers of World War I as "Wipers" and now spelt Ieper. Every Australian battalion on the Western Front at some point marched through the Menin Gate of Ypres on the way to the misery of the Passchendaele quagmire and other points within the Ypres Salient, a bulge in the German lines.
Historians still argue about how many British, Commonwealth and German lives were sacrificed there during World War I. Hundreds of thousands, certainly. No one takes issue with the proposition that it was for nothing. The pitiful few miles of churned, squelching and destroyed ground gained by the British and Commonwealth forces were all recaptured by the Germans within a few months.
It took nine years before the Menin Gate of Ypres, the stone portal to a watery hell destroyed in the war, was rebuilt. It was dedicated to the 350,000 British and Commonwealth soldiers who died in the area and inscribed upon its stone are the names of more than 54,000 of them still "missing", with no known grave.
The names of 6191 men of the Australian Imperial Force are there. The vanished.
The Australian artist Will Longstaff went to the opening of the Menin Gate memorial in 1927 and, having taken a midnight walk along the Menin Road towards Passchendaele, he painted in a single session the most haunting of works: Menin Gate at Midnight, also known as Ghosts of Menin Gate.
Beneath the great gate and a troubled purple night sky drift ranks of disembodied, spectral soldiers; helmets floating in nothingness.
The painting hangs now beneath spotlights in a darkened gallery in the Australian War Memorial.
Across the world, the people of Ypres have never allowed the memories of the lost to die, either.
Every evening since 1927 - apart from a period in World War II when German soldiers once again occupied the city - a small band of buglers has marched to the Menin Gate to play the Last Post.
Most of the buglers are members of the local fire brigade: simple men wishing to bid goodnight, every night, to the long-ago vanished.
Years ago I was fortunate enough to accompany a group of very old Australian veterans - all long gone now - returning to the battlefields of their youth, and as we stood beneath the Menin Gate and the quavering notes of the bugles echoed off the stone, the eyes of those ancient men closed, their thoughts turned to a place we might hope never to know.
This week, with Anzac Day almost upon us, the Australian War Memorial began a new nightly ritual of its own.
From now on as the memorial begins closing down for the evening at 4.50pm, a piper will play the Lament, and the story of one of the 102,000 names inscribed on the memorial's honour roll will be read. One evening it might be the life story of a nurse, the next a sailor, the next a soldier or an airman; plucked from any of the wars in which Australians have fought and died. Finally, a bugler will play the Last Post.
The idea for the ritual came to the memorial all the way from Ypres.
Brendan Nelson, the one-time Liberal leader who spent three years as Australia's ambassador to the European Union, Belgium and Luxembourg, returned to Australia last year to become the new director of the Australian War Memorial in December.
While living in Belgium, Nelson found himself much taken by the night-time buglers of Ypres. He attended the Last Post ceremonies at the Menin Gate no less than 73 times. And as he stood there beneath the stone gate, he says he found himself wondering about the untold stories of all those names from long ago on the walls.
And so, when he returned to Australia, he decided the stories of Australia's war dead should be told. All 102,000 of them. They are available, resting in official records, private papers and diaries within the memorial's vast collection and within the voluminous files of the Australian National Archives.
Night after night those stories will unfold, and then the Last Post, the traditional military signal of the end of the day and, for the dead, a reminder that their duty is done, will be played.
My grandfather's story will not be told. He managed to survive and return home to Australia. But like many of those burdened with the personal knowledge of war, he never glorified it. It was too personal, too painful. A boy, slipping away into the mud, enmity all gone in a cry for help.
The war memorial will not easily run out of stories to tell - certainly not in our lifetimes, or those of our children or grandchildren. The 102,000 stories behind the names currently on the Roll of Honour are enough for 279 years of nightly rituals.
The evening closing ceremony will be streamed live on the memorial's website: awm.gov.au/