There is much difficulty in determining the extent of the area of hostile operations in a manner satisfactory to belligerents and to neutrals. With the increasing range of guns this area has correspondingly enlarged. The speed and endurance of vessels of war has also influenced the extent of effective control. Effective scouting has with the system of wireless telegraphy become much extended. A wireless apparatus may be of great service even though far removed from the immediate area of hostilities. The location of the apparatus is not determinable as are the generally fixed termini of the wire systems. The point at which the wireless equipment may be is not always the important element in the transmission of the message. The nature of the service rendered seems to be the main question. The service may be of as much or possibly of more advantage to a belligerent if the apparatus is several hundred miles distant, rather than near the scene of hostilities, e. g., it may be of greatest importance for a belligerent whose forces are somewhat separated to know a considerable time in advance of the approach of the enemy, in order that the separated forces may be concentrated. To fix an area outside of which wireless service, whatever its character, is free does not seem feasible in actual practice.

It is evident that persons who engage in the transmission of wireless messages cannot properly be regarded and treated as spies. (See Situation VII, International Law Situations, Naval War College, 1904.)

It is also evident from the Chifu incident and from the tendency of opinion that a neutral is responsible to a reasonable extent for the establishment on its territory of stations for the operation of wireless telegraphy. The state can accordingly exercise such control over these stations as may seem expedient.

U. S. Naval War College Discussions, 1907, p. 173, 174.

Summary. From practice, as shown in various states, from the opinions of the courts and of writers, from the votes of conferences and from international agreements, it is evident that the state within whose jurisdiction a wireless telegraph apparatus is or passes, is and will be authorized to exercise a degree of control over its use. The responsibility resting upon such state will be large.

In order to avoid possible complications in time of war it will be expedient in time of war for states, whether neutral or belligerent, to exercise control over wireless telegraphy as circumstances seem to require. There seems to be good ground for the following general principles of action:

1. All private wireless stations within the jurisdiction of a state shall exist under license and subject to regulation by that state.

2. The private stations within the jurisdiction of a state may be closed, appropriated, or placed under censorship by the government in time of war.

3. Private vessels of any nationality in time of war may be required to render inoperative their wireless apparatus when within or on entering the jurisdiction of a state, whether the state is a neutral or belligerent, and the apparatus shall thus remain while the vessel is within the state's jurisdiction unless otherwise ordered.

4. Private vessels having wireless apparatus and ignorant of the declaration of war are entitled to notification before any penalty shall be inflicted.

(a) A belligerent may regulate or prohibit the use of wireless telegraph within the area of hostilities.

(b) A neutral state should use reasonable care to prevent within its jurisdiction the unneutral use of wireless telegraph.

(c) Unneutral use of wireless telegraph on board a vessel makes the vessel liable to the penalty of capture by a belligerent, or to confiscation or sequestration of the apparatus, or of the vessel, or of both by a neutral.

(d) A vessel intentionally aiding a belligerent by the use of wireless telegraph is liable to penalty until the end of the war.

U. S. Naval War College Discussions 1907, pp. 175, 176.

Questions arising in connection with the Use of Wireless Telegraphy. This invention, like that of aerial navigation, has given rise to a variety of new questions in international law, some of which still remain unsolved. These include: (1) The question of the right of a belligerent to erect and use an installation of this kind on neutral territory. This, if at any time open to doubt, is now set at rest by the Hague Convention, No. 5 of 1907, which expressly forbids its exercise by a belligerent, or its allowance by neutrals. (2) The question of whether the use of wireless telegraphy in circumstances similar to those of the Haimun, can be accounted as espionage. As to this it has already been pointed out that the claim to treat the sending of messages by war correspondents to neutral countries for public information as espionage is altogether unwarrantable. (3) The question of the liability incurred by the interception at sea of wireless messages sent by one belligerent and their communication to the other, or by the transmission of false messages. Such acts if done by the enemy would, of course, be quite legitimate; and, if done openly, could not lawfully be treated as espionage. If done on a neutral private vessel they would amount to "unneutral" or "hostile" service, according to the nature of the employment, and would then involve the penalties attaching to those forms of service respectively. If done on a

neutral warship, they would constitute a breach of neutral duty, for which reparation and the punishment of the offenders might be demanded. (4) The question of the use of wireless telegraphy by a neutral vessel for the purpose of communicating with a blockaded port in a matter affecting the operations of war. Such a proceeding would appear to constitute either a violation of the blockade, or an act of "unneutral" service, and would in any case be a lawful ground for condemnation. (5) Finally, there is the question of the right of belligerents to prevent neutral private vessels, on the high seas but within the sphere of belligerent operations, from using such apparatus for the conveying of general news. As to this, no such right is so far established, but the imposing of restrictions similar to those attaching to war correspondence on land would appear to be warrantable both by reason of the necessities of the case and in the light of existing analogies. In effect, this would mean a right to exclude such vessels from an area to be defined, although capable of variation by notice, except on condition of being licensed and of operating under the direction and control of the belligerent granting the license."

Cobbett, pt. II, pp. 459, 460.

If circumstances require and to the extent that you deem indispensable, you may give notice to merchant vessels equipped with wireless, that are within the zone of your operations or even crossing it, that they are forbidden:

To transmit information respecting your position or your movements;

To register telegrams, either plain or in cipher, coming from your vessel or the vessels of your naval force;

To send out signals of a nature to disturb your communications. You will then fix by a declaration and a notification, analogous to those concerning blockade, the geographical limits and, when necessary, the limit of time or hours between which your prohibitions are to be served.

If, in spite of your notification, the ships above referred to transmit forbidden information or systematically disturb your communications, you will act according to the gravity and the consequences of their acts, either as provided in Article 4 of Convention X of The Hague for the application to maritime warfare of the principles of the Geneva Convention, or as indicated for the second case referred to in paragraph 55 (Unneutral Service).

You may therefore demand that these vessels depart outside the limits fixed in your declaration, impose upon them a given direction, detain them, even capture them, and, in any case, seize their wireless apparatus.

If search of these vessels reveals to you simply the register of forbidden dispatches, you may seize their register of messages, require them to depart, fix a particular direction for them and, if you have sufficient reason to suspect their good faith, seize their wireless apparatus.

French Naval Instructions, 1912, secs. 119–121.

[For the provisions of Hague Convention V, 1907, relative to wireless telegraphy apparatus, and citations thereunder, see The Laws of Neutrality, United States Government Printing Office, 1918, pp. 39, 91-94, and 175.]

AERIAL WARFARE.

1. Aerial war is allowed, but on the condition that it does not present for the persons or property of the peaceable population greater dangers than land or sea warfare.

Institute (1911), p. 171.

ARTICLE 1. Belligerent States have the right to carry out warlike acts in any and every part of the atmosphere above their several territories, above the open sea, and above the sea bounding their coasts.

They are forbidden to carry out hostile acts, capable of causing the fall of projectiles or of causing damage generally, above the territories of neutral States, at whatever height, and also in the neighborhood of these States within a radius determined by the force of the cannon of the aircraft.

A belligerent's military aircraft, and also his public non-military aircraft, may not circulate above a neutral State except with the latter's authority. But both public and private aircraft are forbidden to remain above a neutral country within a certain radius of the other belligerent's frontier. The circulation of aircraft in war time is subject to the same restrictions as during peace.

ARTICLE 2. Privateering is forbidden in aerial as in maritime war. Belligerents may, however, incorporate in their military forces, private aircraft and their crews, on condition that they are placed under the control of a duly commissioned officer and carry a distinctive, external sign of their character.

ARTICLE 3. The conversion of private aircraft into military aircraft may be made during war in the territory or in the territorial waters of the State to which they belong, in the territory occupied by the troops of that State, in the open sea, and in the atmosphere not situated above a neutral State, under the conditions laid down in the Hague Convention of October 18, 1907, relative to the conversion of merchant ships into war-ships.

The converted aircraft will preserve their military character during the whole period of hostilities and cannot be reconverted into private aircraft during that period.

ARTICLE 4. The terms of the first section, Chapter II, and of the second section, Chapters I and III, of the Hague Regulations of October 18, 1907, concerning the laws and customs of war on land, besides those expressly laid down in the following articles, will apply, as far as possible, to aerial war.