Cinchona in the year 1851. Mr. [Thaddäus] Haenke mentioned the existence of cinchona bark on his visit to Yuracares in 1796". (Source: Exploration of the Valley of the Amazon, by Lieut. Lardner Gibbon, USN. Vol.II, Ch.6, pp. 146-47.) The cultivation of cinchona led from the 1890s to a decline in the price of quinine but the quality and production of raw bark by the Dutch in Indonesia led them to dominate world markets. The producers of processed drugs in Europe (especially Germany) however bargained and caused fluctuations in prices which led to a Dutch-led Cinchona Agreement in 1913 that ensured a
Therapeutice Specialis ad Febres Periodicas Perniciosas who first systematically studied the effect of cinchona in the treatment of malaria, wrote a book which he titled "Therapeutice Specialis ad Febres Periodicas Perniciosas". One highlight of the "Therapeutice Specialis" is the drawing "tree of fevers", where different fevers, such as branches of the tree, are divided into categories: on the left, those that respond to cinchona, are shown as branches covered with bark, while on the right are those for which cinchona is ineffective, and are depicted as denuded leafless branches. Torti clearly identified cinchona as a specific therapy for intermittent fevers, as opposed to continued fevers, which