124 FOREST CULTURE AND 
material from this colony. The work should be ac- 
cessible in this Museum to all interested in wood- 
work. 
How much we have yet to learn of the value of our 
forest products is instanced when we now know from 
Spanish physicians to combat ague with Eucalyptus- 
leaves, or when Count Maillard de Marafy, from ex- 
periments instituted this year in Egypt, announced 
to us that Eucalyptus-leaves can be used as a substi- 
tute for Sumach. (Egypte Agricole, 1870.) 
Already, in the earlier part of this lecture, I spoke 
of the Peru Bark plants ; but the Cinchonas are not 
all of the same kind. Some endure a lower degree 
of temperature than others, some are richer in qui- 
nine, others richer in cinchonine, others in quinoi- 
dine; and this again is much subject to fluctuations 
under different effects of climate and soil. Great er- 
rors may be committed, and have been committed, 
by adopting from among a number of species the least 
valuable, or one under ordinary circumstances almost 
devoid of alkaloid, though a representative of the 
genus cinchona, and not unlike the lucrative species. 
When calculations in India prognosticate the almost 
incredible annual return of one hundred and thirty 
per cent., after four years, on the original outlay for 
Cinchona plantation, it is supposed that the conditions 
for this new industrial culture are to the utmost favor- 
able. That one of the best species did not thrive 
there at all in proportion to expectations is owing, in 
my opinion, to geologic conditions. The Cinchonas 
before you, reared in soil from our Fern-tree gullies, 
I intended to have tested for the percentage of their 
alkaloids prior to this eyening ; but the timely per- 
