CHAPTER LVIII. 
THE MEDICINAL PROPERTIES OF THE TREES OF THE 
UNITED STATES. 
Tue following chapter has been prepared for this 
work at my request, by Messrs. Parke Davis & Co., man- 
ufacturing chemists, of Detroit, Michigan. I was led 
to solicit the aid of this firm in the preparation of this 
portion of my work through the reputation which it has 
achieved in investigating the medicinal properties of the 
indigenous flora. Prior to its efforts there had been no 
systematic attempt in this direction, and such additions 
to the materia medica as had been made from this source 
were largely through accidental acquaintance with the 
medicinal virtues of particular drugs. Messrs. Parke 
Davis & Co. have for several years been investigating 
our flora, and while they have found many to be of 
negative medicinal value, the list of those which have 
proven serviceable is sufficiently large and important 
to have made a success of their laudable undertaking. 
These investigations referred to have, moreover, peculiar- 
ly fitted them for the task which they have kindly as- 
sumed in connection with this book. 
As might naturally have been expected of a country 
of the dimensions of the United States, with its diversity 
of climate and soil, and the variety in the physical con- 
formation of its territory, the variety of its medicinal 
flora is great. Nature has in no sense of the word been 
remiss in her bestowal of medicinal blessings to the peo- 
ple of this country, and, while we are not fully com- 
