“PASSING THE BUCK”

The phrase “passing the buck” comes from poker where a token, called a
buck, indicated the dealer. According to the Random House Historical
Dictionary of American Slang, when It was the next person’s turn to deal,
you passed the buck. Theoretically, someone who didn’t want the
responsibility of dealing could pass the buck to another player. The
term seems to come into use around the time of the Civil War. Mark
Twain’s Roughing It (1871) says, “I reckon I can’t call that hand. Ante
and pass the buck.”

‘A SHOT OF WHISKEY’

In the old west a .45 cartridge for a six-gun cost 12 cents, so did a glass of
whiskey. If a cowhand was low on cash he would often give the bartender a
cartridge in exchange for a drink. This became known as a "shot" of whiskey.

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                  Picture correction: .45 Colt cartridge