Halfway through World war two for some reason known only to them my parents left the safety of the countryside and moved to the centre of London about a mile or so from these guns(3.7s) stationed in Hyde Park. There were many more than the two seen in this photo plus a battery of rocket launchers. This was after the blitz but German bombers still visited at night then all hell would be let loose,the noise was frightening and as children we were got up and had to sleep down in the basement not that we did as for an hour or two the deafening roar of the guns was non stop making a solid barrage. But what goes up must come down and it was in the form of shrapnel that ended up in rooftops (most houses had many leaks from broken tiles by the end of the war)or in the streets.Any schoolboy worth his salt had a vast collection of shrapnel for swapping etc so the morning after, we would be out searching the streets for more, all fears forgotten for another day.
Ten years later as part of my national service in the army I was firing these very same world war two guns down in Wales.More like boys toys then and very enjoyable! I found that if you stood close behind the gun when it fired you could see the shell going up,but you got a bloody awful headache after a while for your pains.