The anti-monopolist. [volume] (Saint Paul, Minn.) 1874-1878, 1876-04-06
FORESTS AND RAINFALL.

The question Of the influence Of forests on
the NEUROLOGY Of region is one that has
been warmly discussed. Some men of
science, Beoquerel for example, hold that
forests increase the amount Of water receiv-
ed by the soil; while others, Marshal Vail
liant among them, assert that forests dimin-
ish quantity. Some Swans, such as NJ
Matthew, sub-direcior Of the Nancy School
of Forestry. have endeavored, by way ex
pertinent, to get together such facts as
might, if they did not set the question at
rest, at least clear up some points and sup
ply portion Of the experimental date need
ed for full explanation at some future
time NJ Matthew undertook to determine
the amount of rain water received by the
soils OF two neighboring districts, one Of
them covered with timber and the other
arabic land; and to find out weather, in con-
sequence Of the covering Of trees which in
tercepts the rain water, the soil Of the
woodland is as abundantly watered as that
OF the OPEN His conclusion u.s. that tim
bered soils receive as much, and more, rain
water than the open country.
These experiments are Of great import
ance; the result obtained are noteworthy,
and, taken in connection with Becquerels
observations, seem to be decisive Of the
question. Still, in order to meet IN object
ION that might be raised against this mode
Of experimenting, viz, the difficulty Of
finding two districts near to one another and
fairly comparable, we have made expert
ments from another point Of view, which
confirm those made by N. Matthew.
No matter how you select two neighbor-
ing districts, it is not easy to prove that
they arc absolutely comparable to one an
other. The amount Of rainfall may be SER
iously affected by the altitude, and particu-
larry the relative altitude; BY the situation
Of the district; by the relief and con6gura-
ton Of the land in the surrounding country;
and by other unknown conditions which
may in greater or less degree change the
direction or the velocity Of the rain-current
or the point and degree Of condensation Of
the waiery vspor contained in it.
". Dausse, in . memoir which appeared
in the ..Annales des Points ct Chaussees,"
uses the following argument: "Rain is
formed when . warm and humid wind comes
in contract with strata Of cold air; and since
the air Of forests is colder and more humid
than that Of the open, rain must fall there
in greater abundance.
To gauge experimentally the influence Of
forests on the rainfall Of . district, or, in
other words. to ascertain the condensing
power Of forests, We have compared the re-
suits obtained in observation made: l. Above
the forest; and 2. At the same altitude, and
u 20 small distance from the forest. that
any observable difference could.be sitribut-
Cd only 70 the influence Of the latter.
We nov made the following observations
in the heart Of The forest Of Halatte, which
embraces 1000 hectares Of land. At the
height Of about SIX metres (ssy 20 feet)
above groups Of oaks and hornbeans eight
or nine metres high, We placed pluviome-
. psychrometer, maximum and fsisimun
Thermometers, and IN evaporoneter, - -
10 ascertain q that poist the amount Of
rainfall, the degree Of saturAiion Of the air,
and the rate Of temperature and Of evapors
ton.
In the open air. Il tie distance Of only
400 metres from the forest, and u the same
height above the ground - in the former
eass, ~ placed similar instrumeuts under
the same condition. With regard to ths
raiafall asd the degree u ssiarssion, ~
give summary Of he frss six aasahS -
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