Canning method
Sprinkle alum over sliced cucumbers, sliced onions, and diced peppers. Cover with ice and soak for 3 hours. Drain and rinse before canning Bring to boil, sugar, turmeric, mustard seed and vinegar. Add cucumber mixture to brine mixture. Bring to second boil. Pack pint jars with product.
Pour hot brine over product, leaving 1/2-inch headspace and seal jars. Process jars for 10 minutes in a hot water bath.
Processing: As published by Mrs. Wages: "Process jars for 10 minutes" (boiling water bath canner) - 10 minutes.