In many divinations, the Dark Powers are expected to transmit their verdict or message through certain materials which, by their magical associations, are peculiarly fit for the purpose: ashes which retain something of the still-living dead, or ashes of the hearth-fire, the focus of the family’s past and present life; and salt.
In the Isle of Man, for instance, ash from the house fire was carried on the person to ward off evil influences, it was strewn on the earth or floor in the form of a ring, for the same purpose as a defensive circle was drawn by necromancers. Conversely, ash was scattered about anything which was suspected of uncanniness, to restrict its power for harm.
Salt is universally used to negate dangerous and corruptive forces, and a hundred examples of its employment in folk-custom could be quoted. Manx people carried a small quantity in the pocket especially when likely to be exposed to risk from witches or fairies. For the same reason it was sprinkled lightly over provisions, and over farm implements and sea tackle, particularly the nets. It was — and perhaps still is occasionally — thrown into the kitchen fire to allay a storm.
Salt was also used as a medium through which Fate declared its intentions. On Old Christmas Eve (Twelfth Night, 6th January) it was a custom a few years ago in the Parish of Patrick, and doubtless elsewhere, to set upright on the kitchen table a row of thimblefuls of salt. Each heap, moulded by a thimble, stood for a member of the household. If, when the earliest riser came downstairs next morning, any of the salt-heaps was found to have fallen over and scattered, it was understood to be an omen of the death during the coming twelve months of the person whom the heap represented. Those which only leaned a little sideways prefigured an illness or accident, the extent of the list showed whether the affliction would be serious or slight. The person whose salt-heap remained standing upright and uncrumbled could look forward to a fortunate year.
(source: A Second Manx Scrapbook by W Walter Gill (1932); photo)