of the country which we are prepared to defend is what must be called our frontier.
In order to apply this principle to England's Asiatic frontiers, and to explain why they have been so movable, we must now run rapidly along the line which demarcates them at this moment. Passing over the very complicated case of Egypt, we may begin the British Asiatic protectorates with Aden, at the mouth of the Red Sea. From time immemorial the movement of the sea-borne trade between India and Egypt has pivoted, so to speak, upon Aden. It is now the first stepping-stone across the Asiatic waters toward the Anglo-Indian Empire and the westernmost point of English occupation on the Asiatic mainland; and it furnishes a good example in miniature of the manner in which protectorates are formed. We have taken and fortified Aden for the command of the water-passage into the Red Sea; but our actual possession is only a projecting rock like Gibraltar, and so we have established a protective border all round it, within which the Arab tribes are bound by engagements to accept English political ascendency and to admit no other. Not far from Aden lies the protected island of Sokotra, a name in which one can barely recognize the old Greek Dioskorides; and from Aden eastward, round Arabia by Oman to Muscat and the Persian Gulf, the whole coast-line is under British protectorate; the policing of these waters is done by British vessels, and the Arab chiefships along the seaboard defer to England's arbitration in their disputes and acquiesce in her external supremacy.
