The ancient customs were divided into three branches. The first, and, perhaps, the most ancient of all those duties, was that upon wool and leather. It seems to have been chiefly or altogether an exportation duty. When the woollen manufacture came to be established in England, lest the king should lose any part of his customs upon wool by the exportation of woollen cloths, a like duty was imposed upon them. The other two branches were, first, a duty upon wine, which being imposed at so much a-ton, was called a tonnage; and, secondly, a duty upon all other goods, which being imposed at so much a-pound of their supposed value, was called a poundage. In the forty-seventh year of Edward III., a duty of sixpence in the pound was imposed upon all goods exported and imported, except wools, wool-felts, leather, and wines which were subject to particular duties. In the fourteenth of Richard II., this duty was raised to one shilling in the pound; but, three years afterwards, it was again reduced to sixpence. It was raised to eightpence in the second year of Henry IV.; and, in the fourth of the same prince, to one shilling. From this time to the ninth year of William III., this duty continued at one shilling in the pound. The duties of tonnage and poundage were generally granted to the king by one and the same act of parliament, and were called the subsidy of tonnage and poundage. The subsidy of poundage having continued for so long a time at one shilling in the pound, or at five per cent., a subsidy came, in the language of the customs, to denote a general duty of this kind of five per cent. This subsidy, which is now called the old subsidy, still continues to be levied, according to the book of rates established by the twelfth of Charles II. The method of ascertaining, by a book of rates, the value of goods subject to this duty, is said to be older than the time of James I. The new subsidy, imposed by the ninth and tenth of William III., was an additional five per cent. upon the greater part of goods. The one-third and the two-third subsidy made up between them another five per cent. of which they were proportionable parts. The subsidy of 1747 made a fourth five per cent. upon the greater part of goods; and that of 1759, a fifth upon some particular sorts of goods. Besides those five subsidies, a great variety of other duties have occasionally been imposed upon particular sorts of goods, in order sometimes to relieve the exigencies of the state, and sometimes to regulate the trade of the country, according to the principles of the mercantile system.

That system has come gradually more and more into fashion. The old subsidy was imposed indifferently upon exportation, as well as importation. The four subsequent subsidies, as well as the other duties which have since been occasionally imposed upon particular sorts of goods, have, with a few exceptions, been laid altogether upon importation. The greater part of the ancient duties which had been imposed upon the exportation of the goods of home produce and manufacture, have either been lightened or taken away altogether. In most cases, they have been taken away. Bounties have even been given upon the exportation of some of them. Drawbacks, too, sometimes of the whole, and, in most cases, of a part of the duties which are paid upon the importation of foreign goods, have been granted upon their exportation. Only half the duties imposed by the old subsidy upon importation, are drawn back upon exportation; but the whole of those imposed by the latter subsidies and other imposts are, upon the greater parts of the goods, drawn back in the same manner. This growing favour of exportation, and discouragement of importation, have suffered only a few exceptions, which chiefly concern the materials of some manufactures. These our merchants and manufacturers are willing should come as cheap as possible to themselves, and as dear as possible to their rivals and competitors in other countries. Foreign materials are, upon this account, sometimes allowed to be imported duty-free; spanish wool, for example, flax, and raw linen yarn. The exportation of the materials of home produce, and of those which are the particular produce of our colonies, has sometimes been prohibited, and sometimes subjected to higher duties. The exportation of English wool has been prohibited. That of beaver skins, of beaver wool, and of gum-senega, has been subjected to higher duties; Great Britain, by the conquests of Canada and Senegal, having got almost the monopoly of those commodities.

That the mercantile system has not been very favourable to the revenue of the great body of the people, to the annual produce of the land and labour of the country, I have endeavoured to show in the fourth book of this Inquiry. It seems not to have been more favourable to the revenue of the sovereign; so far, at least, as that revenue depends upon the duties of customs.

In consequence of that system, the importation of several sorts of goods has been prohibited altogether. This prohibition has, in some cases, entirely prevented, and in others has very much diminished, the importation of those commodities, by reducing the importers to the necessity of smuggling. It has entirely prevented the importation of foreign wollens; and it has very much diminished that of foreign silks and velvets, In both cases, it has entirely annihilated the revenue of customs which might have been levied upon such importation.

The high duties which have been imposed upon the importation of many different sorts of foreign goods in order to discourage their consumption in Great Britain, have, in many cases, served only to encourage smuggling, and, in all cases, have reduced the revenues of the customs below what more moderate duties would have afforded. The saying of Dr. Swift, that in the arithmetic of the customs, two and two, instead of making four, make sometimes only one, holds perfectly true with regard to such heavy duties, which never could have been imposed, had not the mercantile system taught us, in many cases, to employ taxation as an instrument, not of revenue, but of monopoly.

The bounties which are sometimes given upon the exportation of home produce and manufactures, and the drawbacks which are paid upon the re-exportation of the greater part of foreign goods, have given occasion to many frauds, and to a species of smuggling, more destructive of the public revenue than any other. In order to obtain the bounty or drawback, the goods, it is well known, are sometimes shipped, and sent to sea, but soon afterwards clandestinely re-landed in some other part of the country. The defalcation of the revenue of customs occasioned by bounties and drawbacks, of which a great part are obtained fraudulently, is very great. The gross produce of the customs, in the year which ended on the 5th of January 1755, amounted to £5,068,000. The bounties which were paid out of this revenue, though in that year there was no bounty upon corn, amounted to £167,806. The drawbacks which were paid upon debentures and certificates, to £2,156,800. Bounties and drawbacks together amounted to £2,324,600. In consequence of these deductions, the revenue of the customs amounted only to £2,743,400; from which deducting £287,900 for the expense of management, in salaries and other incidents, the neat revenue of the customs for that year comes out to be £2,455,500. The expense of management, amounts, in this manner, to between five and six per cent. upon the gross revenue of the customs; and to something more than ten per cent. upon what remains of that revenue, after deducting what is paid away in bounties and drawbacks.

Heavy duties being imposed upon almost all goods imported, our merchant importers smuggle as much, and make entry of as little as they can. Our merchant exporters, on the contrary, make entry of more than they export; sometimes out of vanity, and to pass for great dealers in goods which pay no duty gain a bounty back. Our exports, in consequence of these different frauds, appear upon the custom-house books greatly to overbalance our imports, to the unspeakable comfort of those politicians, who measure the national prosperity by what they call the balance of trade.

All goods imported, unless particularly exempted, and such exemptions are not very numerous, are liable to some duties of customs. If any goods are imported, not mentioned in the book of rates, they are taxed at 4s:9¾d. for every twenty shillings value, according to the oath of the importer, that is, nearly at five subsidies, or five poundage duties. The book of rates is extremely comprehensive, and enumerates a great variety of articles, many of them little used, and, therefore, not well known. It is, upon this account, frequently uncertain under what article a particular sort of goods ought to be classed, and, consequently what duty they ought to pay. Mistakes with regard to this sometimes ruin the custom-house officer, and frequently occasion much trouble, expense, and vexation to the importer. In point of perspicuity, precision, and distinctness, therefore, the duties of customs are much inferior to those of excise.

In order that the greater part of the members of any society should contribute to the public revenue, in proportion to their respective expense, it does not seem necessary that every single article of that expense should be taxed. The revenue which is levied by the duties of excise is supposed to fall as equally upon the contributors as that which is levied by the duties of customs; and the duties of excise are imposed upon a few articles only of the most general used and consumption. It has been the opinion of many people, that, by proper management, the duties of customs might likewise, without any loss to the public revenue, and with great advantage to foreign trade, be confined to a few articles only.

The foreign articles, of the most general use and consumption in Great Britain, seem at present to consist chiefly in foreign wines and brandies; in some of the productions of America and the West Indies, sugar, rum, tobacco, cocoa-nuts, etc. and in some of those of the East Indies, tea, coffee, china-ware, spiceries of all kinds, several sorts of piece-goods, etc. These different articles afford, the greater part of the perhaps, at present, revenue which is drawn from the duties of customs. The taxes which at present subsist upon foreign manufactures, if you except those upon the few contained in the foregoing enumeration, have, the greater part of them, been imposed for the purpose, not of revenue, but of monopoly, or to give our own merchants an advantage in the home market. By removing all prohibitions, and by subjecting all foreign manufactures to such moderate taxes, as it was found from experience, afforded upon each article the greatest revenue to the public, our own workmen might still have a considerable advantage in the home market; and many articles, some of which at present afford no revenue to government, and others a very inconsiderable one, might afford a very great one.