The results are well summarised in this passage:
E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
A famous oracle in Epi’ros, and the most ancient of Greece. It was dedicated to Zeus (Jupiter), and situate in the village of Dodna.
The tale is, that Jupiter presented his daughter Theb with two black pigeons which had the gift of human speech. Lemprière tells us that the Greek word peleiai (pigeons) means, in the dialect of the Eprots, old women; so that the two black doves with human voice were two black or African women. One went to Libya, in Africa, and founded the oracle of Jupiter Ammon; the other went to Eprus and founded the oracle of Dodna. We are also told that plates of brass were suspended on the oak trees of Dodona, which being struck by thongs when the wind blew, gave various sounds from which the responses were concocted. It appears that this suggested to the Greeks the phrase Kalkos Dodns (brass of Dodona), meaning a babbler, or one who talks an infinite deal of nothing.
Since ancient times, there have been doubts about whether the doves of Dodona were actual birds or women. Herodotus writes:
...the women who deliver the oracles relate the matter as follows:- "Two black doves flew away from Egyptian Thebes, and while one directed its flight to Libya, the other came to them. She alighted on an oak, and sitting there began to speak with a human voice, and told them that on the spot where she was, there should henceforth be an oracle of Jove. They understood the announcement to be from heaven, so they set to work at once and erected the shrine. The dove which flew to Libya bade the Libyans to establish there the oracle of Ammon."
The Dodonaeans called the women doves because they were foreigners, and seemed to them to make a noise like birds. After a while the dove spoke with a human voice, because the woman, whose foreign talk had previously sounded to them like the chattering of a bird, acquired the power of speaking what they could understand. For how can it be conceived possible that a dove should really speak with the voice of a man?
Frazer mentions "the bronze statuette which ... produced the sound by striking the gong with a clapper" and refers to a paper by Arthur Bernard Cook (The Gong at Dodona, 1902) that presents many ancient sources about the oracle and a reconstruction of the original device:
Strabo, Geography 7 Fragment 3 :
"The proverbial phrase, `the copper vessel in Dodona,' originated thus : In the temple was a copper vessel with a statue of a man situated above it and holding a copper scourge, dedicated by the Korkyraians; the scourge was three-fold and wrought in chain fashion, with bones strung from it; and these bones, striking the copper vessel continuously when they were swung by the winds, would produce tones so long that anyone who measured the time from the beginning of the tone to the end could count to four hundred. Whence, also, the origin of the proverbial term, `the scourge of the Korkyraians.'”
So, in different sources, we find most of the peculiar elements that appear in the card:
* the “bird-person” that could represent the dove-priestess
* the hanging cymbals (“plates of brass were suspended on the oak trees of Dodona”)
* the hovering beaded cords (see Strabo and Cook's reconstruction)
* “striking the gong with a clapper" (Frazer)
The missing element is the “fragment of a flaming branch” (Zucker) below the left foot of the figure. A possible explanation could be a reference to this passage by Pliny the Elder:
The fountain of Jupiter in Dodona, although it is as cold as ice, and extinguishes torches that are plunged into it, yet, if they be brought near it, it kindles them again.