1 lb. each of lentils and POTATOES, 1 large Spanish onion, 1 medium-sized head of celery (or the outer pieces of a head of celery, saving the heart for table use), 1 breakfastcupful of tinned tomatoes or 1/2 lb. of fresh ones, 1 oz. of butter, pepper and salt to taste. Chop the onion up roughly, and fry it in the butter until beginning to brown. Pick and wash the lentils, and set them over the fire with 2 quarts of water or vegetable stock, adding the fried onion. Peel, wash, and cut up the POTATOES, prepare the celery, cut it into small pieces, and add all to the lentils. When they are nearly soft add the tomatoes. When all the ingredients are quite tender rub them through a sieve. Return the SOUP to the Saucepan, add pepper and salt, and more water if the SOUP is too thick. Serve with sippets of toast.
The Allinson Vegetarian Cookery Book, by Thomas R. Allinson (Year 1915)