THE ROLE OF DEPOPULATION, DEFORESTATION, AND 
MALARIA IN THE DECADENCE OF CERTAIN NATIONS.! 
By Dr. Fenix REeNAvtt. 
The persistent decadence of certain peoples is at present attrib- 
uted to depopulation, deforestation, and malaria. How can these so 
widely divergent factors be brought into interrelation? To under- 
stand it, geology, sylviculture, and medicine must be interrogated. 
In the period of her greatness Greece was a fertile, well wooded, 
healthful, and very populous country, estimated by historians to 
have had at least 8,000,000 inhabitants. 
Two centuries later, at the time of the Roman conquest, the 
mightiest cities of Greece and the most important leagues could 
place only a few thousand soldiers in the field, and entire Hellas, 
according to Plutarch, could equip not more than 3,000 fully armed 
troops. The country became poor. Polybius estimates the taxable 
capital of the Peloponnesus at less than 6,000 talents ($7,080,000), 
the landed and movable property of Athens at 5,750 talents ($6,371,- 
000), being half of the reserve funds of Pericles. 
Historians ascribe the depopulation of Hellas to a continuously 
increasing emigration of adult inhabitants. Since the fourth century 
B. C. they went forth in throngs to foreign regions as mercenaries; 
the conquests of Alexander the Great precipitated this exodus and 
dispersed Greece over the surface of Asia. 
Low birth rate probably also played an important part, but we 
are poorly informed on this subject. The classical instance of the 
Spartans who, at the time of the Roman conquest, counted only a 
few hundreds, is not enough, for here is involved only the question of 
the aristocratic caste, and we do not know whether the plebs had 
diminished.? 
Emigration and low birth rate prevailed only for a time. If 
Greece had conserved its fertile soil, immigration or a higher birth 
rate would have sprung up at a given moment and filled up the ranks. 
Depopulation persisted because the land was impoverished by becom- 
ing deforested and unhealthy. Strabo observes that in his time 
' 1 Translated by permission from the Revue Scientifique, Paris, Jan. 10, 1914, pp. 45-48. 
2 Possibly it was due to the high birth rate that Greece, down to the sixth century B. C., swarmed over 
numerous colonies. Families quitted their city to establish new ones. Greece in that way relieved itself 
of an excess of population and at the same time remained populous. On the other hand, at the end of the 
fourth century B.C. the emigration cf adult people was no longer compensated by an excessive birth rate. 
Unfortunately we have no certain data on this subject. 
593 
73176°—sm 1914——38 
