Cooper

one engaged in the business of making barrels, kegs, firkins, casks, butts, or hogsheads. The upright pieces forming the sides of cooperage are called staves. The swelling or bulge at the middle is formed by making each stave a little wider in the middle than at the ends. A skillful cooper shaves his staves, cuts out his heads, and makes the hoops all so exact that when he sets up the staves, puts in the heads, and drives on the hoops, the different parts are a perfect fit without the removal of a shaving. The tapering of the barrel enables the hoops to be driven on tight. The surface, being curved on the principle of an arch, is very much stronger than the same amount of material in the shape of a box. If the staves shrink a little they can be tightened by driving up the hoops. Although the barrel is not a convenient receptacle for storage in a car or ship, no substitute has been found. Wine casks and beer kegs are made of great thickness to withstand the pressure of the fermenting liquid. Casks for vinegar, oil, and syrup require to be strong. Oak is the favorite material for all such cooperage. Nowadays cooper shops employ a great deal of machinery. In the making of flour barrels the only work done by hand is the handling of material and the setting up of the barrels. One of the sights of industrial Minneapolis is the continuous succession of flour barrels coming down a shute from the cooper's shop into the large racks in which they are drawn by two-horse teams to the mills. The driver does not think he has a load until his rack contains 175 barrels. The last United States census reports 2,146 cooper shops, with 22,938 wage earners, and an annual output valued at over $40,000,000. In 1908 a careful writer stated that the American demand for tight cooperage, chiefly from the distilleries, required the yearly manufacture of 267,827,000 staves and 17,774,375 headings, valued at over $12,000,000.