Art. 22. Soldiers not wearing a disguise who have penetrated into the zone of operations of the hostile army, for the purpose of obtaining information, are not considered spies.
Similarly, the following should not be considered spies, if they are captured by the enemy: soldiers (and also civilians, carrying out their mission openly) entrusted with the delivery of dispatches intended either for their own army or for the enemy's army.
To this class belong likewise, if they are captured, persons sent in balloons for the purpose of carrying dispatches and, generally, of maintaining communications between the different parts of an army or a territory.