Cinchona in quinology to examine the contents of these components in assays. The yields of quinine in the cultivated trees were low and it took a while to develop sustainable methods to extract bark. In the meantime Charles Ledger and his native assistant Manuel collected another species from Bolivia. Manuel was caught and beaten by Bolivian officials leading to his death but Ledger obtained seeds of high quality which were offered to the British who were uninterested, leading to the rest being sold to the Dutch. The Dutch saw its value and multiplied the stock. The species later named as "Cinchona
Cinchona la Quina" (1793) with illustrations. He proposed a Spanish expedition to search for plants of commercial value which was approved in 1783 and was continued after his death in 1808 by his nephew Sinforoso Mutis. As demand for the bark increased the trees in the forests began to be destroyed. To maintain their monopoly on cinchona bark, Peru and surrounding countries began outlawing the export of cinchona seeds and saplings beginning in the early 19th century. The Colonial European powers considered growing the plant in other tropical parts. The French mission of 1743, of which de la Condamine was member,