I occasionally walk across Hyde Park to or from my dentist.   Today, it meant that I found myself crossing Hyde Park Corner at lunchtime, giving me an opportunity to admire Charles Jagger’s astonishing monument to the artillery in the first world war.   I know that everyone else already knows and understands the historical and artistic significance of this work.   But, seen in the midday sun, I found it very moving to see this great monument to the suffering of the Great War, the names of the battlefields carved in stone, the single soldiers standing in commemoration, the bas reliefs showing scenes of battle.   It’s a gun salute in stone: