(A) means a racoon, a small American animal valued for
its fur. It is about the size of a fox, and lodges in hollow trees.
A gone coon.
A person in a terrible fix; one on the verge of ruin. The coon
being hunted for its fur is a “gone
coon” when it has no escape from its pursuers. It is said that
Colonel Crockett was one day out
racoon-shooting in North America, when he levelled his gun at a
tree where an “old coon” was concealed. Knowing the colonel's prowess,
it cried out, in the voice of a man, “Hallo, there! air you Colonel
Crockett? for if you air, I'll jist come down, or I know I am a gone
Martin Scott, lieutenant-general of the United States, is said to
have had a prior claim to this saying.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894