In ancient times—and long before this government existed—civilized and commercial nations had codes or laws which related especially to transactions upon the sea. Those respecting ships of war and warlike operations at sea were called the laws of Admiralty; those respecting vessels engaged in commercial affairs were called Maritime laws; and the courts empowered with jurisdiction to hear and try causes, or to take any judicial proceedings in those cases, were styled Courts of Admiralty and Maritime Jurisdiction. These laws, in many respects, differed so materially from the laws relating to affairs on land, that the authority and power to take proceedings in and adjudicate upon them was conferred upon a particular class of courts. Hence we see the origin of the names of such tribunals. In this country the United States District Courts have been[437] designated by the laws as the courts which shall have original and exclusive authority to adjudicate this class of causes; yet an a............