THE LONGEVITY OF TREES. 73 
there was no demand for them ; and our diligent attempt to 
find a single copy in the public and private libraries of three 
of our largest cities has proved entirely unsuccessful. 
The foundation of the North American Sylva was laid by 
the laborious researches of the elder Michaux; who, under 
the auspices of the French government, devoted ten years, 
from 1785 to 1796, to a thorough exploration of the country, 
from the sunny, sub-tropical groves of Florida to the cold 
and inhospitable shores of Hudson’s Bay ; repeatedly visiting 
nearly all the higher peaks and deepest recesses of the Alle- 
ghany Mountains, and extending his toilsome journeys west- 
ward to the prairies of Illinois and the banks of the Missis- 
sippi. He had formed indeed, and was only prevented by 
untoward circumstances from executing, a plan — more hardy 
than we can well conceive at this late day —for ascending 
the Missouri to its sources, and crossing the mountains into 
the then untrodden but now litigated country on the Oregon. 
The curious reader will find an extract from his private diary 
in the “ American Journal of Science and Arts” for January, 
1842 ;1 showing that he had laid his plans and proposals upon 
this subject before Mr. Jefferson, who was then Secretary of 
State. The papers submitted by him may have suggested the 
scheme of the national expedition of discovery, soon after- 
wards ordered by Jefferson, and nobly carried into effect by 
Lewis and Clarke. 
Soon after his return to France, and the year before he 
fell a victim to scientific zeal upon the coast of Madagascar, 
the elder Michaux published his History of North American 
Oaks ;? which may be deemed the nucleus of the more com- 
prehensive work subsequently published by his son. The 
younger Michaux accompanied his father in the earlier por- 
tion of his travels, through South Carolina, Georgia, and 
Florida ; but he afterwards returned to Europe. Revisiting 
this country in the autumn of 1801, and passing the winter 
in South Carolina, he traveled, during the following season, 
1 Vol. xlii. p. 7. 
2 «“ Histoire des Chénes de l’Amérique Septentrionale.” Par A. Mi- 
chaux. Paris, 1801. 1 vol. fol. 
