PREFACE. 



which are powerful in Europe, comparatively inactive in 

 other climates. The heat of a country, its humidity, par- 

 ticular localities, food, and the social habits of a people will 

 predispose them to varieties of disease for which the drugs 

 of Europe offer no sufficient remedy, and will render that 

 which is relied ' upon in one country unworthy of de- 

 pendence in another. Thus the Cinchona bark of Peru, 

 important as it is in Europe, is, we are told, rejected by 

 the people among whom it grows, because it is found too 

 stimulating and heating for their excitable constitutions. 

 And speaking of Ipecacuanha Dr. Von Martius, who so 

 carefully examined practically the Materia Medica of 

 Brazil, asserts " nullum est dubium quin Emetica in terris 

 zonae fervidae subjectis effectus producent multo magis 

 salutares quam in regionibus frigidioribus." 



This last observation seems to indicate, that if emetic 

 plants are so much more common in hot than cold countries; 

 it is because there is so much greater a necessity for them. 

 The late Mr. Burnett, and many other persons, have as- 

 serted that every country spontaneously furnishes remedies 

 for those maladies which the people of the soil are natu- 

 rally subject to, and that the foreign drugs imported into 

 the markets of Europe would soon be superseded to a 

 great extent, if the properties of European plants were 

 carefully examined. It is contended, in illustration of this 

 opinion, that Salicine, obtained from our native Willows 

 is equal in energy to Quinine, and that it is formed by 

 Providence in low marshy places, exactly where remittent 

 and intermittent fevers are experienced most frequently, 

 and with the greatest severity. It is not for the author to 

 offer an opinion upon a point of this sort ; his business 

 here is only with facts, or what are believed to be facts. It 

 is, however, deserving of notice, that if England is already 

 found to yield species of such powerful action as Hellebore, 

 Hemlock, Henbane, Belladonna, Stramonium, Foxglove, 

 Willow bark, Holly leaves, Spurge Laurel, Centaury, Col- 

 chicum, Bryony, Ergot, and many more, it becomes 

 probable that other powerful agents still remain to be 



