21. Watches are extensively manufactured in various parts of Europe, but particularly in French Switzerland, France, and England. The London watchmakers have been celebrated for good workmanship, for more than a century and a half. This manufacture has not yet been commenced in the United States, although the machinery, or _inside work_, is very often imported in tin boxes, and afterwards supplied with dial plates and cases. This is especially the case with the more valuable kinds of watches. 22. Brass clocks are manufactured in most of our cities, and in many of our villages, and wooden clocks, in great numbers, in the state of Connecticut. These last are carried by pedlers into the remotest parts of the country, so that almost every farmer in our land can divide the day by the oscillations of the pendulum. [Illustration: COPPERSMITH.] THE COPPERSMITH, THE BUTTON-MAKER, AND THE PIN-MAKER. COPPER. 1. Copper is a ductile and malleable metal, of a pale yellowish red color. It is sometimes found in a native state, but not in great quantities. The copper of commerce is principally extracted from the ores called sulphurets. Copper mines are wrought in many countries; but those of Sweden are said to furnish the purest copper of commerce, although those of the island of Anglesea are said to be the richest. 2. In working sulphureted ore, it is first broken into pieces, and roasted with a moderate heat in a kiln, to free it from sulphur. When the ore is also largely combined with arsenic, a greater degree of heat is necessary. In such a case, it is spread upon a large floor of a reverberatory furnace, and exposed to a greater heat. By this treatment, the sulphur and arsenic are soon driven off. 3. The ore is then transferred to the fusing furnace, and smelted in contact with fuel. The specific gravity of the copper, causes it to sink beneath the _scoria_ into a receptacle at the bottom of the furnace. To render the metal sufficiently pure, it requires repeated fusions, and, even after these, it usually contains a little lead, and a small portion of antimony. 4. _Alloys of copper._--Copper is combined by fusion with a great number of metals, and, in such combinations, it is of great importance in the arts. When added in small quantities to gold and silver, it increases their hardness, without materially injuring their color, or diminishing their malleability. An alloy, called white copper, imported from China, and denominated, in that country, _pakfong_, is composed of copper, zinc, nickel, and iron. It is very tough and malleable, and is easily cast, hammered, and polished. When well manufactured, it is very white, and as little liable to oxydation as silver.