Dr. Adolf Gutsmuth was buried alive several times to demonstrate a safety coffin of his own design, and in 1822 he stayed underground for several hours and even ate a meal of soup, bratwurst, marzipan, sauerkraut, spätzle, beer, and for dessert, prinzregententorte, delivered to him through the coffin's feeding tube. The 1820s also saw the use of "portable death chambers" in Germany. A small chamber, equipped with a bell for signalling and a window for viewing the body, was constructed over an empty grave. Watchmen would check each day for signs of life or decomposition in each of the chambers. If the bell was rung the "body" could be immediately removed, but if the watchman observed signs of putrefaction in the corpse, a door in the floor of the chamber could be opened and the body would drop down into the grave. A panel could then be slid in to cover the grave and the upper chamber removed and reused.