Remove the seeds from the peppers and the tomatoes. Slice the tomatoes and the cucumbers, and chop the peppers and onions fine; sprinkle with the salt and let stand for twenty-four hours. Drain the vegetables, pour the vinegar and water over them, bring slowly to a boil and drain again.
Make a smooth paste as follows: Mix three tablespoonfuls of sugar, one teaspoonful of powdered cinnamon, one teaspoonful of turmeric, one-fourth teaspoonful of powdered cloves, one-fourth teaspoonful of powdered allspice, with a little cold vinegar; bring one pint of vinegar to boiling point, add two tablespoonfuls of chopped mint, two tablespoonfuls of white mustard seeds, the spices and then the vegetables and let cook for twenty minutes, stirring constantly.
Pour into glass jars and seal at once.