Freeze up again.
Tonight I went down to Bourne Mill about 6 o’clock. It was very dark, but many searchlights were out, and almost as soon as I got there Anti-Aircraft guns began firing over in the direction of Mersea. I could neither see nor hear any planes, but the firing kept up for nearly an hour. You could see the double flashes of gun and shell, and then hear the double, coughing explosion.
A good many people were walking about at the time, but seemed quite unperturbed by it. No alarms were sounded, and when I got back up town the place was full of people. No sign of any “yellow” warning being given to the ARP people, but I stood by at the Castle until about half past 8, and moved on several cars which tried to obstruct the gates.
Eric's friend, Hervey Benham, records in his account, 'Essex at War' (p20), that German aircraft were laying magnetic mines off the coast of Essex during these early months of the war and this may have been the cause of the anti-aircraft defences being fired from Mersea Island on this occasion.
A yellow ARP warning was a preliminary and confidential warning issued to ARP, police and fire services ahead of a full-scale air-raid warning. The yellow warning was issued when enemy planes were within 15 minutes flying time of a District's boundaries. Despite the lack of warning, Eric was still undertaking his duties as a Special Constable in case of the need to open the air raid shelters at Colchester Castle.