While historical support is given to the maintenance of a monopoly as in France, it is not probable that the system will find imitators in other states, however tempting the returns obtained might seem. Great Britain has by her insular position solved the problem in another way. By interdicting the domestic cultivation of tobacco, all that is consumed must be imported, and a customs duty offers a ready instrument for making the plant, in whatever form it enters, contribute its dues to the exchequer. In Russia, as in the United States, where tobacco is a domestic product, the tax is imposed upon its manufacture, and this method requires supervision but no monopoly of the state. The tobacco _régime_ is defended almost entirely on fiscal grounds, and as a monopoly, an extreme measure, has proved its value as an instrument of taxation. Other reasons, of a moral character, are urged to induce the state to monopolize the manufacture and sale of distilled spirits. Both France and Germany have considered this question, and, in spite of confident predictions of a large profit, have decided not to undertake it. Russia, on the other hand, has taken it up quite as much on social as on revenue grounds, and is gradually securing a monopoly of the trade in spirits. The initial cost of the undertaking is large, and, as the system has not yet been perfected, it is too early to give a judgment on its availability as a financial instrument. The transit dues, once commonly used by different countries, have been generally abandoned, and in China must they be sought for in their original forms of vexatious and unprofitable force. They arose from a desire to derive some benefit from a commerce permitted grudgingly, and rarely attaining any high results. The same end was sought by duties on exports, much employed when the country was supposed to be drained of its wealth by what was sent out of it. The conditions necessary for a successful duty on exports are not often found, and only in a few countries are they now existent. In Italy, South America, and Asia, exports of certain natural products are taxed, and, as in the case of Brazil, yield a notable revenue. In view of the rapid advancement of production in new countries and of inventions in the old, whereby many natural monopolies have been destroyed and competition made more general, such duties prove to be more obstructive to trade than productive of revenue, and are rapidly being abandoned. In spite of a formal prohibition of export duties in the Constitution of the United States, they are sometimes suggested in all seriousness.