I think the coolest explanation is that they were some kind of two way radio.John T wrote:
Perhaps the Halakah or Haggadah has some information?
I don't even know how to do a word search within those sources.
A while back, I criticized Dufi for saying Haggadah -
You (and he) probably meant to say Aggadah -is a Jewish text that sets forth the order of the Passover Seder.
Technically, as Dufi pointed out, the two words are the same as "Ha" means "the" in Hebrew, however he was just trying to defend his silly choice of terms.refers to the homiletic and non-legalistic exegetical texts in the classical rabbinic literature of Judaism, particularly as recorded in the Talmud and Midrash.
Halakha -
.It includes the 613 mitzvot ("commandments"), subsequent talmudic and rabbinic law and the customs and traditions compiled in the Shulchan_Aruch
Actually the simplest place to look is the Talmud, but I really doubt there is any Halakha involved with these - maybe wash your hands before handling them after a bowel movement.
Searching for information is very difficult and should only be attempted by someone with insight, and erudition.
I went to https://scholar.google.com/scholar?q=ur ... sdt=0%2C31
The Rabbis apparently feel that the Urim and Thummim were not around during the Second Temple. My guess is that any magical powers were added later.