To perform these calculations, the Chinese have an arithmetical board, or abacus, called _swan-pan_, or “_counting-board_,” on which, by constant practice, they will perform calculations in numbers with surprising facility. It consists of an oblong frame of wood, having a bar running lengthwise about two thirds of its width from one side. Through this bar, at right angles, are inserted a number of parallel wires, having moveable balls on them, five on one side, and two on the other. The principle on which computations are made, is this; that any ball in the larger compartment, being placed against the bar and called unity, decreases or increases by tenths, hundredths, &c.; and the corresponding balls in the smaller divisions, by fifths, fiftieths, &c.: if one in the smaller compartment is placed against the middle bar, the opposite unit or integer, which may be any one of the digits, is multiplied by five. [Sidenote: OPIUM.] Having heretofore cursorily alluded to the vast sum annually expended in the importation of opium, I now proceed to give a more particular statement concerning the trade, the number of smokers, &c., &c. The opium-trade, which scarcely attracted the notice of merchants previously to the year 1816, has now swollen into great importance, by the rapid and extensive sale of one of the most destructive narcotics which the world ever knew, and which is used in China as a pernicious indulgence, by smoking. The government has passed the most rigorous laws to prevent its importation and use, but as the officers of the revenue boats, from Linting and Cap-shuy-moon to Canton, are bribed, and receive a stipulated fee on every chest of opium, and every other article illegally imported, smuggling is no longer fraught with any material risk, and has at length assumed the appearance of a regular branch of commerce. Once in two or three years, the Chinese admiral is ordered to proceed to the smuggling depots at the island of Linting, (alias Ling-ting) the “Solitary Vail,” or the “Destitute Orphan,” or to Cap-sin-moon, alias, Cap-shuy-moon, or the “Swift water passage,” and exterminate the “foreign barbarians.” He goes down in formidable array, with an immense number of flags flying; and the sound proceeding from an endless number of great gongs and other noisy instruments, is heard, with a favourable wind, long before his fleet “heaves in sight;” the smugglers are previously informed of his coming, (for public notice is given many weeks, perhaps months, before he arrives;) the imperial fleet is then hove to, at a safe distance, far beyond the reach of cannon-shot, from three to five miles; the gongs are then beaten with the utmost fury, the trumpets blown, and the thousands of warriors shout and bellow with loud vociferations, to frighten away the monsters, and a cannon-shot or two is fired, perhaps; the “_barbarians_” then get under way very leisurely with a topsail or two