Firemen belonging to an insurance office, which gave a badge charged with a phoenix: these men were called likewise firedrakes.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Philistines * Phos BottleNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes