Certain classes of merchandise, such as arms and ammunition, which, by the rules of international law, cannot lawfully be furnished or carried by a neutral nation to either of two belligerents; if found in transit in neutral vessels, such goods may be seized and condemned for violation of neutrality. The Pet- erhoff. 5 Wall. 5S, 18 L. Ed. 504 ; Richardson v. Insurance Co., 0 Mass. 114, 4 Am. Dec. 92. A recent American author on international law says that, “by the term ‘contraband of war,’ we now understand a class of articles of commerce which neutrals are prohibited from furnishing to either one of the belligerents, for the reason that, by so doing, injury is done to the other belligerent;” and he treats of the subject, chiefly, in its relation to commerce upon the high seas. Hall. Int. Law, 570. .192; El- rod v. Alexander, 4 Heisk. (Tenn.) 345.