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 a region is one that has
been warmly discussed Some men Of
science, Becquerel 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 dilnln-
ish quantity. Some savans, such as NJ
Matthew, sub-director Of the Nancy School
of Forestry. have endeavored, by way ex
pertinent, to get together such facts as
might, ii they did not Sc; the question at
rest, al least clear up some points and sup
ply a p%oIti.n Of the experimental date need
ed for q full explanation AZ some future
time. NJ Matthew undertook to determine
the amount OF rain water received hy the
soils 0, Two reighboring districts, one Of
them covered with timber and the other
arabic land; and 10 find out weather, IN con
sequence OF the covering Of trees which in
tercepls the rain. water, the soil of the
woodland is as abundantly watered as that
0. the open" HIS conclusion is, that tim
berei soils receive az 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 Becquerel g
observations, seem to be decisive Of the
question. Stiil, in order to meet an object
ION that might be raised asains. this mode
Of experimenting, VIZ, the difhculfy Of
finding two districts near TO one another and
fairly comparable, we have made expert
ments from another poin, Of view, which
confirm those made by NJ Matthew.
No matter how you selec; two neighbor-
ing districts. it is not easy 10 prove that
| they arc absolutely comparable to one an
other. The amount Of rainfall msy be ser
iously affected by the altitude, and particu-
larry the relative altitude; by the situation
of the district; by the relief and confgura-
ton Of The land in the surrounding country;
and by other unknown conditions which
nay in 4 greater or less degree change the
direction. or the velocity Of the rain-current
or the point and degree Of condensation Of
the saiery vapor contained IN H.
n. Dausee, in . memoir which appeared
in the "Aunales dee Ponts e, Chaussees,"
uses the following argument: "Kain Is
formed when a 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 mus. fall there
in greater abundance.
To gauge e~xperimentally the influence Of
forests on the rainfall Of q district, or, in
other words. 70 ascertain the c~ondensinx
po~er o. forests. we have compared the re-
suits obtained in observation made: l. Above
the forest; and 2. A; he same altitude, and
., 60 small . distance from the forest. that
| any observable difference could be a,iribut-
ed only TO the influence Of the latter.
We now made the following observations
in the heart Of the forest Of Halatie, which
embraces 900 hectares Of land. At the
| height Of abou: SIX metres (say % feet)
above . groupe Of oaks and hornbeams eight
or nine metres high, we placed 3 plu.iome-
. psycnrometer, maximum and minimum
thermometers, and an evaporometer, 90 az
TO ascertain At that point the amount o!
rainfall, the degree Of saiuraiion Of the air
and the rate Of temperature and Of svapora
ton.
In the open air. ., ne distance Of only
300 metres from the forest, and ~ the sAms
heigh. above tns ground SO in the former
case, ne PLACED similar instruments under
The sane condition With regard 70 tbs
rainfall and the degree Of sstur.tion, ~.
give . summary Of the frss six nssths' oh.
~oeSvsiicnS, - lollewe