A: Jason has been given the walking paper.

B: Really? He’s doing all right, I think.

A: I heard it through the grapevine.

Note: Grapevine refers to “an informal person-to-person means of circulating information or gossip” or “a secret source of information.” The grapevine, a metaphor, originally refers to the telephone line. In the early days of U.S. telegraphy, companies rushed to put up telegraph poles, some actually using trees rather than poles. To some, the tangled wires resembled the wild vines found in California. During the U.S. Civil War the telegraph was used extensively, but the messages were sometime unreliable, hence the association of rumors with grapevines. The phrase first appeared in print in 1852.