The Declaration of St. Petersburg, inasmuch as it is capable of indefinite expansion, is a somewhat awkward precedent for those who in their hearts love war and shield its continuance with apologetic platitudes. How, they ask, can you enforce agreements between nations? But this argument begins to totter when we remember that there is absolutely no superior power or tribunal in existence which can enforce the observance of the St. Petersburg Declaration beyond the conscience of the signatory Powers. It follows, therefore, that if international agreements are of value, there is no need to stop short at this or that bullet: which makes the arbitration-tribunal loom in the distance perceptibly nearer than it did before. At first sight, this agreement excluding the use of explosive bullets would seem to favour the theory of those who see in every increase in the peril of war the best hope of its ultimate cessation. A famous American statesman is reported to have said, and actually to have appealed to the invention of gunpowder in support of his statement, that every discovery in the art of war has, from this point of view, a life-saving and peace-promoting influence.[1] But it is difficult to conceive a greater delusion. The whole history of war is against it; for what has that history been but the steady increase of the pains and perils of war, as more effective weapons of destruction have succeeded one another? The delusion cannot be better dispelled than by consideration of the facts that follow. It has often seemed as if humanity were about to get the better of the logical tendency of the military art. The Lateran Council of 1139 (a sort of European congress in its day) not only condemned Arnold of Brescia to be burnt for heresy, but anathematised the cross-bow for its inhumanity. It forbade its use in Christian warfare as alike hateful to God and destructive of mankind.[2] Several brave princes disdained to employ cross-bow shooters, and Innocent III. confirmed the prohibition on the ground that it was not fair to inflict on an enemy more than the least possible injury.[3] The long-bow consequently came into greater use. But Richard I., in spite of Popes or Councils or Chivalry, revived the use of the cross-bow in Europe; nor, though his death by one himself was regarded as a judgment from Heaven, did its use from that time decline till the arquebus and then the musket took its place. Cannons and bombs were at first called diabolical, because they suggested the malice of the enemy of mankind, or serpentines, because they seemed worse than the poison of serpents.[4] But even cannons were at first only used against fortified walls, and there is a tradition of the first occasion when they were directed against men.[5] And torpedoes, now used without scruple, were called infamous and infernal when, under the name of American Turtles, they were first tried by the American Colonies against the ships of their mother country.