=The Great Secret.=--The actual discovery of the composition of true porcelain by Böttger is interwoven with romance, and the betrayal of the secret processes of its manufacture at Meissen to the leading factories of Europe is a record filled with stirring incidents of the most piquant character. The story of young Böttger, the alchemist and inventor, is told in full by Professor Ernst Zimmermann, Keeper of the Royal Porcelain Collection at Dresden, _Die Erfindung und Frühzeit des Meissner Porzellans_, Berlin, 1908. The search for the philosopher's stone to transmute baser metals into gold had fascinated all chemists. Böttger was credited with more knowledge than he possessed, and he hastily quitted Berlin to avoid the too assiduous attentions of the King of Prussia. For years he wandered in Saxony, and finally claimed protection in 1701 from Frederick Augustus, Elector of Saxony. His life at the laboratory at Meissen, under Ehrenfried Walter von Tschirnhaus, who was a distinguished scientific scholar, was that of a guarded prisoner with a wonderful secret. Tschirnhaus, who was a good chemist, established a glass furnace and invented an ingenious burning mirror, and had essayed to make porcelain. But on the assumption that it was a vitrification, his results only led him to the production of a milky glass. A specimen of this _milch glass_ is in the Japanese Palace at Dresden. When Charles XII of Sweden invaded Saxony, Böttger and his workmen were hurried off to the impregnable fortress of Königstein, where a laboratory was erected. A year later he was back at Meissen conducting experiments and cheerfully exhorting the workmen. In 1709 he produced his true hard porcelain from natural earth obtained from Aue, near Schneeberg. The most elaborate precautions were taken at Meissen to prevent the secret becoming known. The earth was delivered in sealed casks. It was in vain that an oath was exacted from each workman and written on the walls--"Silence until death" (_Geheim bis ins grab_). The punishment for betrayal was incarceration as a State prisoner in the fortress of Königsberg for life. The terrible silent conditions of the labour produced a longing on the part of the immured workmen to escape. And escape they did. =The Secret divulged.=--In 1718, the year previous to Böttger's death Stolzel, the chief workman at Meissen, made his way to Vienna and proceeded to establish, under the direction of a Belgian named Claude Du Pasquier, a manufactory of hard porcelain. The factory was acquired for the State by the Empress Maria Theresa in 1744. From Vienna a workman named Ringler carried the secret far and wide. His name is linked with the founding of several factories--at Höchst in 1740, at Frankenthal in 1754, where he became director, at Nymphenberg in 1756, where his aid was invoked, at Ludwigsberg (in Würtemberg) in 1758, and at Zurich in 1759.