In 1864 William Leighton of J. H. Hobbs, Brockunier, & Co. in West Virginia perfected a formula for an inexpensive soda-based glass that was as crystalline as the heavy lead glass previously used for most American-made clear glass items. This new glass revolutionized the pressed glass tableware industry, and probably was responsible for the flood of clear glass medicinal and household bottles that followed the Civil War. Like earlier clear glass, the improved lime glass was tinted with manganese oxide to remove its natural green coloring. Clear glass items manufactured with manganese tend to turn varying shades of lavender when left exposed to the sun. Manganese was imported from Germany in the nineteenth century to decolor glass and was no longer used after the outbreak of World War I. In the immediate post-Civil War period, the American glass industry expanded rapidly. Molds were improved and worker and furnace productivity increased to many times their 1800 level. New bottle shapes were introduced, and specialized and embossed bottles proliferated. The manufacture of preserve jars became a major industry, and a special “blow-back” mold, included in John Mason’s 1858 fruit jar patent, was used to form the screw threads for the sealable lids. Standard bottle shapes for different products became common, as did uniformly applied standard lip forms for different purposes. The standard shapes of the bottles from the Middleton Place privy are shown in Figure 16. Turnmolding, a long-known method of removing mold marks by rotating the unfinished bottle in the mold, became a popular way of manufacturing unblemished wine bottles. A popular technique of embossing was plate-molding, an operation in which a personalized name plate could be inserted into a standard mold for inexpensive lettering of even small runs of bottles. [Illustration: Figure 16. Bottle shapes from the Middleton Place privy (not to scale). A. Champagne beer. B. Export beer. C. Malt whiskey. D. Jo-Jo flask. E. Union Oval flask. F. Bordeaux wine. G. Hock wine. H. Olive oil. I. American preserve. J. Fluted extract. K. Bromo-Seltzer. L. Poison. M. French square. N. Baltimore oval. O. Philadelphia oval. P. Double Philadelphia oval. Q. Plain oval. R. Panel. S. Ball neck panel. T. Oil panel. U. Round prescription. V. Quinine. W. Morphine. X. Free-blown apothecary’s vial. Y. Round patch box. Z. Ointment. AA. Stoneware ink. BB. Bell mucilage. CC. Cone ink. DD. Cylinder ink.]