Considering these facts, in connection with the rule that the aerial bombardment of all defended towns is permissible, it would seem that the whole of belligerent territory-especially the invaded territory—will in a way be placed on the firing line. Non-combatants in a danger zone will no longer be able to find comparative safety in cellars, because most of the projectiles will have a high angle of fall and all bombs and demolished aircraft will fall vertically, or nearly so. There will be no absolute security for life and property anywhere within the cruising radius of belligerent forces. A general realization of this fact may operate as a deterrent of war by causing the populations of embittered states to weigh more carefully than heretofore the grave question of hostilities.

As regards aerial-maritime combats, the belligerents may not engage in operations that involve the transit of projectiles through the air space above a neutral marginal sea, or the fall of projectiles or matériel thereinto. M. von Bar has proposed that aerial combats should not be permitted above the marginal sea of belligerents, except above the area of operations of a blockade, because neutral vessels, which have the right of innocent passage through such waters, might be endangered. 10 It is not probable that this rule will receive general sanction. Neutral vessels that navigate belligerent waters do so at their own risk, and navigation by them for any considerable distance through the marginal sea is such an exception as not to necessitate a modification of the old rule. As commercial vessels are not ordinarily permitted to engage in the coasting trade of a foreign state, they generally cut straight across a foreign marginal sea off the port of destination. During a naval combat, a merchant vessel, anywhere in the vicinity, can almost invariably escape danger by changing her course. This will not necessarily be so in the case of a supra-marine combat. M. von Bar has therefore proposed that aerial combats over the high seas should be restricted to a radius of 20 kilometers (12 miles) from the scene of a naval combat.11 As in the case of aerial-land warfare, hostile aircraft may often meet at a much greater distance than twelve miles from a belligerent zone below, and it can hardly be expected that such an encounter will not result in

10 Art. 2 and footnote to Art. 2 of the rules submitted by M. von Bar to the Institute of International Law in 1911.

11 Art. 2 (b. 1) of the rules submitted to the Institute of International Law in 1911.

combat. Perhaps a more acceptable rule would be one providing that aerial personnel operating at a greater distance than twelve miles from a belligerent zone, must so conduct their operations as not to imperil neutral vessels; and that if any damage to neutral life and property should result, the case could be referred to the Permanent Court of The Hague for adjudication. Any such damage could only result from carelessness. It should not be more difficult for aerial craft to conduct their supra-marine hostilities without endangering innocent life and property than for coast artillery in time of peace to conduct their target practice seaward without imperiling shipping.

" 12

Many of The Hague regulations relative to "Means of Injuring the Enemy" are also applicable to hostilities involving aircraft. The new warfare will, of course, bring in its train special devices to meet new conditions. To illustrate. While a belligerent aircraft should properly have distinctive markings and carry the national flag, it would be a legitimate ruse to seek to deceive the enemy by ascending to such a height as to render distinctive characteristics invisible from below. Owing to the difficulty belligerent personnel ashore and afloat will have in recognizing their own aircraft-especially when returning from a long flight, special means of identifying them will be devised. These will generally consist of certain evolutions made in a definite way and order. They will, of course, be confidential, but an enterprising enemy will seek to discover and to employ them in order to deceive his adversary. An explosive incendiary bullet has recently been invented with the object of exploding the inflammable gas used to sustain an airship. The result of such an explosion would be comparable to that of a mine. Such a bullet penetrating the human body would probably cause frightful agony, unless death were instantaneous. Nevertheless, the bullet will probably not be barred, because it is not "calculated to cause unnecessary suffering." 13

Although it has frequently been proposed to extend the marine league so as to include a total width of ten or twelve miles to accord with the range of modern cannon, there is no real necessity therefor; because, no matter how far extended, belligerents would not be permitted to join

12 Section II, Chapter I, Annex 4 H. C. (1907).

18 Art. 23 (e), Annex, 4 H. C. (1907).

battle in such a manner, that projectiles fell even within the outer edge of the extended marginal sea. There is no practical reason why a state in time of peace should care to control the sea for more than a marine league from its coast, and in time of war the exceptional case where such control is considered desirable could be provided for by a special rule. A wider marginal sea would only involve greater responsibilities without compensating advantages. No detailed information as to military dispositions can be gleaned from a marine vessel on the high seas just beyond the marine league, or, for that matter, within the marine league; but an aircraft at a considerably greater distance than a league could profitably observe such dispositions. For example: a foreign aviator five miles or more off Sandy Hook could observe every detail of our coast defenses located there. Great Britain has led the way by claiming jurisdiction over the air space above her marginal sea. If her object was to prevent espionage of coast military districts, she has not claimed a sufficient width of air space. It seems reasonable that a state should be permitted to exercise jurisdiction over sufficient air space seaward to prevent espionage. There is no relation, however, between the width of this space and that of the marginal sea, for the two widths are founded on entirely different considerations. A rule, therefore, should be formulated extending territorial air space the necessary distance seaward. Twenty kilometers (twelve miles) seem a reasonable limit. Von Bar's employment of that number as the limiting distance of an aerial combat from a naval combat has given the number a quasi-standing in international law, and it is probable that, by employing telescopic lenses, valuable observations could be made on coast defenses from that distance at sea. In special circumstances a belligerent state may find it desirable to establish a "defense" or "strategical" area off one of its ports in order to prevent espionage on its naval strength and dispositions. If the entire closure of such an area should seriously hamper commerce, it is customary to allow neutral vessels to pass through the zone at stated hours and by prescribed routes. The precedent for establishing such areasextending them seaward, in some instances as far as ten miles-was set by Japan during the Russo-Japanese War of 1904.14 It is fair to assume that such special jurisdiction has received the sanction of international 14 International Law Situations, 1912, Naval War College, pp. 122-129.

law, for no remonstrances against the Japanese ordinances were filed. If it becomes necessary for a belligerent to assume maritime jurisdiction for a distance greater than a league from his coast in order to prevent espionage from marine vessels, there is no good reason why he should not assume jurisdiction over the air space for a distance of 12 miles (20 kilometers) further in order to prevent espionage from aircraft. The question of extending the seaward limit of aerial jurisdiction-general and special—is a matter of such importance to Powers within aerialcruising range of one another as to require consideration at the next Hague Conference.

Some writers have attempted to extend to aerial craft the laws of maritime warfare relating to the treatment of commercial vessels. Such attempts lead to impracticable results and unnecessary complications. In return for the privileges granted to belligerents in the way of preempting air spaces over the high seas for hostilities, they should not be permitted to interfere in any way with neutral aircraft outside of such spaces, except perhaps to exercise a right of approach with a view of determining belligerent or non-belligerent character. It is neither practicable nor worth while for aircraft to engage in contraband trade, render unneutral service, or break blockade. As for the first, the amount of cargo that can be carried is negligible, and freights would be prohibitiye. No form of unneutral service of any value-short of actual participation in hostilities can be rendered by an aircraft. The transmission of information or dispatches by neutral carriers has lost whatever importance it ever had. Belligerent aircraft are better fitted for the task than private aircraft; and mail steamers, submarine cables, telegraph lines, and radiotelegraphy offer still better facilities. The transportation of military persons by neutral aircraft on behalf of a belligerent would be as foolhardy as unnecessary under the conditions of modern warfare. The question has been debated as to whether, under the Declaration of London, a blockade can be effective unless the blockading fleet prevents access to the enemy coast by aircraft. There is no doubt that the delegates to the London Conference had in mind access by marine vessels only, and hence a prize court would probably hold that aerial access would not invalidate the blockade. However, no Power will in the future attempt a blockade unless one or more vessels carry hydro-aeroplanes

in sufficient number to punish attempts to enter the air space above the area of blockade.

It has been held that a private aircraft which is captured at sea, must be sent in with its personnel to a prize court for adjudication.15 This assumption is obviously based on the rule that all private property captured at sea by a belligerent war vessel must be adjudicated by a national prize court; but all precedents deal with the capture of marine vessels only, and the reason for the rule was the protection of innocent commerce. However, if there is any doubt as to what procedure should be followed, aircraft and their personnel should, by international convention, be specifically excluded from prize court jurisdiction, this for three reasons. First: Since no neutral commerce is involved, the question to be decided is whether or not there has been an intrusion by neutrals into belligerent operations at sea. Army tribunals deal with such questions on land, and there is no reason why naval tribunals cannot be entrusted with the same powers. Second: If captured neutral aeronauts believe they have been treated too severely, or that the capture took place beyond the limits of belligerent jurisdiction, the matter could be taken up by the neutral government concerned by diplomatic representation, or by presenting its claims to the Permanent Court of Arbitration at The Hague. Third: It is not, in general, practicable to send an aircraft into a prize court. In most cases, the craft will be wrecked when it falls into the hands of a naval force, and nothing can be done with it except to abandon it or stow the wreckage on a war vessel, where space is precious. If the craft is not wrecked, it will probably be beyond cruising distance of one of the belligerent's home ports. If it is within cruising distance, who will navigate it,-the captured personnel placed on their honor, or a prize crew of sailors unacquainted with aircraft in general, and foreign ones in particular? And finally there will be no "papers" for a court to pass on.

The attempt to carry into the air the laws of contraband, unneutral service, and blockade might lead to results detrimental to humanitarian interests. The rule that neutral vessels may render assistance to belligerents, without incurring any penalty beyond the condemnation of the property involved, is unfortunately entrenched in international law. 15 See International Law Situations, 1912, pp. 90-91.