I always find Remembrance Day services moving.

But the part that gives me a lump in the throat is when the solitary bugler plays The Last Post.

I think much of my emotional response can be traced back to my childhood. My paternal grandfather lived with us during his final years. He was in his late 70s by then and was a veteran of the First World War, having served in Palestine.

I was under the age of 10.

He had a stack of military band LPs which we used to play on his little, battered record player. We loved the stirring marches played by the bands of the Coldstream Guards and the Royal Marines and I pretended I was a soldier marching up and down, slowly wearing a trench in his carpet.

But the moment that affected us most was when we played a recording of The Last Post and I pretended to take down an imaginary flag. My grandfather had demonstrated how I should do it and I would concentrate hard to copy him.

He would choke up as the plaintive bugle notes rose solemnly from the record player and I vividly remember being moved by his reaction.

I was recalling all this this week as another Remembrance Day came and I heard The Last Post.

I realised I didn’t know the history of this brief, haunting piece of music.

Of all the customs in our country surrounding how we remember those who died in war, I’m most familiar with the poem For The Fallen. I know Laurence Binyon’s famous stanza by heart - ‘At the going down of the sun...’. I used to live near the house where Binyon was born and often thought about his words when I walked past the plaque on the wall.

But the origins of The Last Post were a mystery to me.

As with these things, the explanation is obvious once you know.

The practice of calling the last post is used in British Army camps to signal the end of the day.

Inspection of all the sentry posts begins with the first post call and the last post call is sounded when the final sentry has been inspected. This custom dates back to the 17th century.

Various tunes have been used, but the one we know and associate with remembrance services was, I understand, adopted after the First World War and was meant to be a calling of the spirits of the fallen to the cenotaph as well as signifying the end of war - ‘the going down of the sun’.

I researched who composed the piece, but it would appear it is a traditional bugle tune that has been handed down along with other military pieces, such as Reveille, used to wake the troops.

I stand to be corrected on this, so if you know otherwise, do let me know.