The British sausage is called a banger because in the First World War it was so full of water that it exploded in the pan, and the one that never did was the one from Cumberland. Before the war a butcher's sausage was pork, fat, salt, pepper and a little rusk to hold it, and it fried. During the war, with meat rationed, the makers filled the skins with water, scraps and whatever cereal they could get, and the water turned to steam in the hot fat and burst the casing. Soldiers named it, and the name stuck to the whole family for a hundred years. The Cumberland sausage stood apart. Up in the Lake District it was made by the yard, coiled flat into a wheel rather than twisted into links, from coarsely chopped pork rather than minced slurry, heavily peppered, with no colouring and almost no filler. A proper one is more than 90% meat. The spice came in through Whitehaven, which was trading with the Indies, and the pork came from the pigs every Cumbrian farmhouse kept. You bought it by length, not by number. If you grew up in the north it was the Sunday breakfast, a whole coil in the pan, cut into quarters at the table, with the fat spitting round it. Fried in lard, because that is what was in the pan. In 2011 the name was protected by law. It has to be made in Cumbria, in the coil, with at least 80% meat, and the cheap imitations with a quarter of the pig and three quarters of the water had to drop the name. The sausage in a supermarket pack is what the war taught the trade: fill the skin with water and sell the skin. The one in the coil is what a sausage was before anyone had to. They told you sausages were bad for you. They meant the water.