16 Afterwards The Jesuits Used It; Hence It Is Sometimes Called

Jesuit's bark. It was brought most particularly into notice when

Louis XIV of France purchased of Sir R. Talbor, an Englishman, his

heretofore secret remedy for intermittent fever, and made it

public.



There are various barks in commerce classified under the head of

Peruvian barks. Their great value depends upon the presence of

certain alkaloid substances called quinine, cinchonine, and

quinidine, which exist in the bark in combination with tannic and

other acids. Quinine is the most useful of these alkaloids, and

this is found in greatest quantities in Calisaya bark. The gray

bark of Huanuco is derived from _Cinchona micrantha_, which is

characterized by its yield of cinchonine, and the Loxa or Loja

barks are furnished in part by _Cinchona officinalis_, and are

especially rich in quinidine. There is some uncertainty about the

trees that produce the various kinds of bark. These trees grow in

the forests of Bolivia and Peru, at various elevations on the

mountains, but chiefly in sheltered mountain valleys, and all of

them at a considerable distance below the frost or snow line. They

are destroyed by the slightest frost. Plants of various species

have been distributed from time to time, in localities which

seemed most favorable to their growth, but all reports from these

distributions have, so far, been discouraging.