All seem to agree in excluding the first class from neutral trade; and, in general, admitting the second.  The chief difference is about the third class.  The last kind of articles—­for example, money, provisions, ships, and naval stores, according to Grotius, are sometimes lawful articles of neutral trade, and sometimes not; and the question depends upon circumstances.  This is perhaps the truest ground of decision, as we shall see in subsequent illustrations.[166]

Thus, these articles become contraband, ipso facto, if carried to a besieged town, camp, or port.  So in a naval war, ships and materials for ships, are contraband, although timber and cordage may be used for other purposes, besides fitting out ships of war; and so horses and saddles are not of necessity warlike stores, except when comparing the quality, manufacture, or quantity attempted to be imported into the hostile state, with the circumstances and condition of the war, it appears (if not to be impossible) to be in the highest degree unlikely, that they should be designed for any other purposes besides the purposes of war.[167]

[Sidenote:  Provisions, when Contraband.]

Common Provisions are not Contraband in general prize law, except in the single case of being sent to a beseiged or blockaded place.[168]

It is a modern practice, in order to remove all possible doubt as to what goods are contraband, for nations at war to enumerate them particularly in treaties or compacts with neutral states; and such treaties leave the neutral, with which they are made, at liberty to supply the enemy with all goods that are not enumerated in them.  These treaties do not operate as a law; but like other treaties, are binding only between the nations that are parties to them.[169]

[Sidenote:  Lord Stowell’s Opinion on Contraband of War.]

The Opinions of our great English authority, Lord Stowell, on this subject, are contained in two judgments, of which the following is the substance:—­

“In 1673, many unwarrantable rules were laid down by public authority respecting Contraband.  It was expressly asserted by a person of great knowledge and experience in the English Admiralty, that by its practice corn, wine, and oil, were liable to be deemed contraband.  In much later times, many sorts of provisions, such as butter, salted fish, and rice, have been condemned as Contraband.  The modern established rule was, that generally they are not contraband, but may become so under circumstances arising out of the peculiar situation of the war, or the condition of the parties engaged in it; among the causes which tend to prevent provisions from being treated as contraband, one is that they are of the growth of the country which exports them.

“Another circumstance, to which some indulgence, by the practice of nations, is shown, is where the articles are in their native and unmanufactured state.  Thus, iron is