What must a sentry do according to the 8th General Order?

The 8th General Order instructs a sentry to give the alarm in case of fire or disorder. This emphasizes the responsibility of a sentry to ensure the safety and security of the area they are guarding. Being vigilant and alert to potential threats, including fires and disruptions, is a crucial part of maintaining order and protecting both personnel and property.

This order underscores the proactive role a sentry must take in alerting others to emergencies or situations that could endanger others. Maintaining constant awareness and readiness to communicate threats is vital for an effective sentry. In contrast, the other choices relate to additional duties but are not the focus of the 8th General Order, leading to their exclusion as correct answers.