"I hear the men are striking."

"What for?"

"Shorter hours."

"Luck to them. I always did think sixty minutes was too long for an hour."

Notes
Luck to them:祝他们成功。

Did the striking men think sixty minutes was too long for an hour?
that's the key of this jape.
Shorter Hours
1、缩短工时；
2、一小时六十分钟应该缩短（这样一来也能达到目的，全人类的工时都缩短了，一劳永逸）。