On the qui vive

The political influence wielded by many of the court ladies, and especially by the first lady-in-waiting (mother of the present Emperor), bears a certain resemblance to that which the eunuchs wielded under the later Manchus at the court of Peking. […] And behind the 30 ladies-in-waiting there are the rank and file of female palace attendants, some 300, all of Kyoto stock—quite sufficient to keep any conscientious chamberlain on the qui vive.

The question of who pressed the bell that sounded in Erskine's room, in the night, was a great source of worry to Watt, for a time, and kept him awake at night, on the qui vive.