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replanted, and no more scirocco occurred. The mistral, in the 
South of France, which did not occur till after the clearing of 
the Cevennes — the unhealthiness caused in Alsace by the felling 
of trees on a large scale — the aridity of Provence, once the 
garden of France, due to the same causes, are all cases in point. 
At the time of the Revolution, writes Michelet, began a 
general destruction of forests in France. Trees were sacrificed 
for the most trifling uses. Two pines would be felled for the 
making of a pair of sabots ! Some curious statistics are given 
by another writer on the effect of trees upon population, it 
being shown that in some departments the population has 
steadily decreased since the clearing of the forests. So late 
as 1853 the prefet of the Basses Alpes wrote officially: “If 
prompt and energetic measures are not taken to prevent this 
destruction, we shall be able to foretell almost exactly when the 
French Alps will become a desert in consequence of this icono- 
clasm.” But no instance is more striking than that of Algeria. 
At the time of the conquest the whole of the Sahel and a great 
part of the Metidja were covered with wood and scrub, which 
not only prevented undue evaporation from the earth, but also 
acted as a condenser of moisture, causing refreshing dews and 
rains. The destruction of forests, dating from 1845, has mate- 
rially changed the atmospheric conditions in those districts, and 
nothing but ignorance, cupidity, and fanaticism can account for 
the wholesale forest-burning still witnessed in Tunis and Al- 
geria. The Arabs are persistent incendiarists, partly because 
the system enters into their notions of agriculture, but chiefly 
to spite and injure the constantly widening circle of European 
colonization. Forty thousand hectares of forest were thus de- 
stroyed in the year 1865 alone. Now, it has been found by ex- 
perience that the Australian Blue Gum Tree, or Eucalyptus 
globulus , answers the purpose of reboisement , or replanting, 
in Algeria better than any other at present known, and many 
leading colonists, as we have seen, have brought wealth, science, 
and philanthropy to bear on the question. Foremost of these 
must be named M. Trottier, who claims pre-eminence for 
the Eucalyptus, on sanitary as well as economic grounds, 
seeing not only in its anti-febrile and climatic properties the 
surest remedy for malaria, but in the valuable quality of its 
timber a perpetually increasing source of wealth to the colony. 
In his various pamphlets, severally entitled “Influence des 
arbres sur la pluie,” “ Notes sur l’Eucalyptus,” “ Role de 
l’Eucalyptus en Algerie,” &c., these matters are fully dealt 
with, and his conclusions may be summed up as follows : — The 
results of special observations made by the pluviometer show 
that forests draw down a greater abundance of rain than culti- 
vated open land ; that even under trees the water reaching the 
