Interior of fifteenth century pharmacy. From Johannis de Cuba’s “Ortus Sanitatis”, Strassburg, 1483. ] [Illustration: THE “ORTUS SANITATIS” OF JOHANNIS DE CUBA, PUBLISHED AT STRASSBURG IN 1483. The woodcut depicts Adam and Eve beneath the “Tree of Knowledge.” ] In the sixteenth century sapphires, emeralds, rubies, garnets, jacinths, coral and sardonyxes were used in all tonics prescribed to protect the heart against the effects of poison and of the plague. As it was noted that these remedies were frequently ineffectual, an explanation was sought in the fact that spurious stones were often used, the apothecaries either not having the knowledge to recognize the genuine stones, or being moved by a desire to profit by the substitution of some inferior substance. Hence physicians were warned to be on their guard against such deceptions, and only to employ thoroughly trustworthy apothecaries for the compounding of their prescriptions. A substitution frequently made was that of the so-called yellow chrysoprase (cerogate), a stained chalcedony, for the jacinth, although the true jacinth of the ancients was of the color of the amethyst. The grinding of coral in a brass mortar, instead of in one of marble, was also regarded as a very dangerous proceeding, which would have the worst possible results for the unlucky patient who took the powder, for some particles of the brass might be rubbed away and mix with the coral. This was said to have often produced very serious illness.[232] In a price-list of a firm of German druggists, printed in 1757, all the precious stones still appear. Here the cost of a pound of rock-crystal is six groschen ($.18); the same quantity of emerald was priced at eight groschen ($.25), while the pound of sapphire was quoted at sixteen groschen ($.50), of ruby at one thaler ($.75), and of lapis lazuli at five thalers ($3.75). This indicates quite clearly the quality of the emerald, sapphire and ruby offered for sale. A pound of Oriental bezoar commanded the highest price, sixteen thalers ($12).[233] Regarding the length of time during which various preparations retained their strength, Braunfels[234] states that, according to the opinion of the Arabian physicians, the solution of lapis Armenus lasted for ten years, while that of lapis lazuli could be preserved only about three years. A list of the indispensable materials which should be in every good pharmacy included the following precious stones: Jacinth Sapphire Emerald Topaz Margaritha (pearl) Magnes Coral Hematite Ætites Jasper