Not my circus

How much fun a barrel of monkeys would actually be would depend on how tightly they were packed and how long they’d been in there. Would this barrel be jam packed? Chock full? How much fun would it be to open a barrel of angry ravenous monkeys? No fun. I don’t even want to think about it. Also, under what system of measurement is the barrel anybody’s standard unit for a quantity of monkeys? Because I happen to know that crabs are measured by the bushel and while they too are eukaryotic bilaterally symmetrical critters, they’re nobody’s simile for hilarity.