AERIAL NAVIGATION, Legal Aspect of. The rapid development of aerial naviga tion seems as yet to have produced no actual decisions upon the novel questions of private right and public regulation which sooner or later will be presented for solution. In the absence of express statute or international regulation by treaty, the principles and anal ogies of the common and maritime law must furnish the rule of decision. The right of an aviator to fly over another's land depends upon the true meaning and present application of the ancient maxim, "Whoever owns the soil owns also to the sky and to the depths' Lit erally construed and applied, any passage over another's land, at whatever height, is a tres pass and therefore unlawful. On the other hand, the view is taken that this maxim is not to be applied literally, that the owner's rights in the air space above his land are appurtenant to the soil and extend only so far as is neces sary to the enjoyment of the use of the soil without interference and that therefore a mere passage across his land at a sufficient height and without other interference is not an actionable wrong. It is everywhere agreed, however,
that if navigation over another's premises is conducted so as to constitute a nuisance, or to result in actual damage, an action will lie: The conflict of opinion is as to whether the right of action is limited to cases of actual damage and of nuisance. An opinion fast gaining ground is that the landowner cannot be heard to complain of any use of the air spaces above his land by which no damage to him can result; that his rights above the height necessary to the, full enjoyment of his land free from any interference are too unsubstan tial to be protected by the law (4 Am. J. Int. L. 126, 127).