Human: What was the name of the wireless operator who began to behave strangely? Assistant: 
The wireless operator who began to behave strangely was named Jeffryes. He was initially a conscientious and respected member of the group, but from mid-June, his behaviour began to deteriorate. He became moody and aggressive, challenging his hut mates to fights, mumbling to himself, developing a persecution mentality and neglecting his hygiene.