What is the fourth order to the sentry?

The fourth order to the sentry is to repeat all calls from any post more distant from the guardhouse or quarterdeck than their own. This order emphasizes the importance of communication and awareness in a military setting. A sentry's responsibilities include not only maintaining vigilance but also ensuring that critical information is relayed efficiently throughout the ranks. By repeating calls from distant posts, the sentry helps maintain coordination and situational awareness among personnel, especially during situations where immediate interpretation of commands may be necessary for the safety and efficiency of operations.

In contrast, the other options focus on specific protocols or actions that are not covered by the fourth order. For example, saluting non-commissioned officers is related to military courtesy and respect, notifying the officer of the deck pertains to safety protocols, and allowing only enlisted personnel to pass deals with access control. While all are important aspects of military duties and conduct, they do not align with the core directive of communication represented in the fourth order.