when the exact value of the rent is known. This involves a very careful examination, and the whole nature of rent must be analyzed. This leads to a long digression on natural rent, which has already been discussed under that heading.
"Custom (ch. vi) is a contribution or excisium out of goods sent out or imported into the prince's dominions (41)." Export duties are only advisable in exceptional cases; i. e., when the country has a natural monopoly, as England has in tin. The duty should be regulated to leave a reasonable profit to the exporter, and to make the price of the commodity lower than it could be had from elsewhere. Customs on imported goods should be governed by the following considerations: All goods ready for consumption are to be made somewhat dearer than the same things grown or made at home. Articles of luxury should be highly taxed. Goods not fully wrought and manufactured, tools and materials used in manufacture, should be gently dealt with (43). The objections to the tax are the cost of collection, the incentive to smuggling and to bribery. The amount so raised can of itself never suffice to bear the expense of the kingdom (44). A substitute for customs might be found in tonnage duties. These are easily collected, and the object on which they are laid is visible to everyone. The state might also undertake a general marine insurance. The profits would be great, and there would be no inducement to evade payment (45). Even if such changes were made, it may be said that the officials of customs must be still employed in the same numbers, to prevent the importation of commodities that are wholly prohibited.