Other mistake: Miss Fisher takes a handwritten phrase in "ancient" Hebrew to one of the main characters to be translated. The writing is actually in cursive Hebrew and is properly written. While performing the translation however, the "expert" translator holds the writing upside down. He also follows the writing with his finger from left to right. Hebrew is written from right to left. (00:32:00)
Ruddy Gore - S1-E6
Other mistake: In this episode set in 1928, a character reads from a 1908 magazine, featuring on the opposite page an ad for an event set to happen in 1930. (00:26:30)
Other mistake: The clock on the lounge's desk signals the same time for the whole scene's duration (when the girls spot the strange woman waiting outside), which lasts much longer than a minute. (00:08:20 - 00:09:50)
Answer: Louisa's watch was broken during the struggle to get away from her attacker.
Bishop73