The sun. [volume] (New York [N.Y.]) 1833-1916, 1914-10-18

pinges upon the mountain slope, Its
most perfect fiuidity causes the mass
of atmosphere, which up to that point
has been flowing slightly tangent to
the curvature of the water level OF
the ocean, TO take the new direction
of the ascending slope and thus to be
lifted to an elevation which exceeds
the highest mountain point by factor
receivable from the momentum OF the
ascending flow of air. Without going
too infinitely into the atmospheric
physics 1t suffices to state that air
which is at balance In a state of satu-
rarion in the temperature normal to tho
coastal plain must discharge fixed pro-
portions OF its content of aqueous va
por when 1t is raised to the lower tenn
perature normal to the altitude to
which it ascends Thus we have the
Blue Mountain forest bathed in rain
or screened in fog, the latter condition
being somewhat more efficient in slim
ulatlng vegetal growth and similarly
less destructive of the humus. These
constants OF the climate OF this mon
tame forest have been very completely
worked out by the author with equal
attention to detail he has investigated
the INTERPOLATION between the normal
precipitation I'm gross and In the fea-
lures of its distribution throughout the
year. the temperature Of the summit
region. and the character OF the vege-
tation which Is best tolerant Of the
definitely determined climatic factors.
These carefully prosecuted researches
are all set forth with cogency In the
several chapters OF Mr.. Shreve's book.
He concludes his case in accordance
with the notation on the brief he holds.
he has established the Blue Mountain
forest as the product OF soil, climate
and altitude interactlng We prefer 10
accept the montana forest Of jamaica
as proved in this excellent work and TO
point briefly to some OF its effects upon
so much OF Jamaica as is agron omically
valuable. therefore to the benefit which
this forest confers upon the people who
make Jamaica their home.
II covers the initial point OF the con-
servation of land and OF water. for II
Is the screen which covers the first
point of Jamaica which receives the
tropical rains. II regulates the flow Of
the rivers which descend from the
mountain slopes, Il holds the dropping
water in the tangle Of It's root growth
and produces continuous flow rather
than sudden food each stem Of herb
and trunk of tree serves as a dam 20
hold the rain against the increment Of
surface velocity and each such dam inn
pounds somewhat Of the soil eroded or
derived in chemical solution and tends
to accumulate a humus. Soil and water
thus are slowly fed toward the lower
lands, where they may he of service
without this protection they would roll
in torrent haste, carrying destruction in
the place Of blessing. and NJ the upper
limit entailng no less destruction In
denudation.
The forces OF nature are never really
wild. There is always seeming destr,ic-
ton. but there is secular poise, a bal.
ance over long periods. II is this sec.
ullr balance which finds its enduring
record IN the story OF past earth
which geology has been showing "a,
since the first revelations Of Hugh MI.
Ter. Such work as Mr. .'hreve has con.
Quoted for the summit Of Jamaica. a,
9'hers are conducting in the relation al
plant life to the earth which support,
/ it. Is not wholly botany. not wholll
climatoloGy. it seems veritahly n Ceol-
ogy Of the present world.