Alectryomancy (also called alectoromancy or alectromancy) is a form of divination in which the diviner observes a bird, several birds, or most preferably a white rooster or cockerel pecking at grain (such as wheat) that the diviner has scattered on the ground. The observer may place grain in the shape of letters and thus discern a divinatory revelation by noting which letters the birds peck at, or the diviner may just interpret the pattern left by the birds’ pecking in randomly scattered grain.
In ancient Rome, fhis practice was used when the sun or the moon was in Aries or Leo. A circle of letters (originally twenty-four in number, since j, v are the same as i, u) was traced on the ground and laid out with some sort of grain placed on each letter. Next a rooster, usually a white one, was allowed to peck at the grains, thus selecting letters to create a divinatory message or sign. The chosen letters could be either read in order of selection, or rearranged to make an anagram. Sometimes readers got 2 or 3 letters and interpreted them.
In another version, the observer tethers the bird in the center of a circle, around the perimeter of which is marked the alphabet, with a piece of grain at each letter. For each grain the bird pecks, the observer writes down the letter which that grain represents. The observer also replaces each grain as the bird eats it, so that letters may be repeated. The sequence of letters recorded will presumably contain a message.
In Africa, a black hen or a gamecock is used, which within such a religious practice and belief “to foresee, to be inspired by a god” may be accurately referred to as a sacred cock or sacred vessel. An African diviner sprinkles grain on the ground and when the bird has finished eating, the seer interprets the designs or patterns left on the ground.
Another method of alectormancy, used less often, was based on reciting letters of the alphabet noting those at which a cock crows. Letters were recorded in sequence and then these letters were interpreted as the answer to the question chosen by seers.
A rare, obsolete meaning of alectormancy is “a divination by a cock-stone”. A cock-stone or alectoria was “a christall coloured stone (as big as a beane) found in the gyzerne, or maw of some cockes” (Cotgrave). These stones, purportedly found in a roosters crop, were known to the Romans and were imputed with magical powers. Apparently, they were used for some sort of lithomantic divination, though the details of this use are not to be found.
Alectormancy was also used in Ancient Rome to identify thieves.