During the first World War England was attacked by Zeppelins and aeroplanes in almost 80 air raids in total. Although the military effect was negligible, the attacks lead to numerous victims among the civilians. Because of the very low accuracy of the bombings the attackers were named 'baby-killers'. The authorities decided to design a warning system but refused to use sirens, because in their opinion this would only lead to panic. Instead policemen in cars (some say with scouts blowing a horn) and on bicycles would drive around with the text "Take Cover" before the attack and "All Clear" if the attack had ended.
The car is a 1915 Overland model 80-T (or perhaps an 81-T), where the T stands for tourer. The Overland badge hasn't been removed by us, but apparently by the authorities for an unknown reason. The tyres seem to be (All-British!) Beldam tyres. The abbreviation SC is still a mystery for me: it could mean something like Safety or Security Corps. Another interesting fact is that the photos of the warning car were published apparently without any restraint in the german press (source not known).
One correct solution for the make came in from Miguel Llorente. Although he suggested the model of the year before, we'll forgive him because the difference is in only very small details.
So, Miguel, congratulations . Please send us your shirt size and mail address.