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it to deteriorate both with respect to its
effects upon the health of man and other
animals and upon the fertility and pro-
ductiveness of the soil." He quotes
from Marsh's well-known work on "Man
and Nature" to the effect that forests
"within their own limits and near their
own borders maintain a more uniform
degree of humidity in the atmosphere
than is observed in cleared ground"' and
he further illustrates this point from
the experience of districts in America,
where the forsts have eben cleared
away: "With the disappearance of the
forest all is changed. At one season the
earth parts with its warmth by radiation
to an open sky, and receives at another
heat from the unobstructed rays of the
sun; hence the climate becomes excessive
and the soil is alternately parched by the
fergour of summer and seared by therig-
ours of winter. Bleak winds sweep
unresisted over its surface, drift away
the show that sheltered it from the frost,
and drup up its scanty moisture."
I have cited Marsh only by way of illus-
tration; for the whole literature of the
subject is full of evidence of the same
kind. Careful observation in recent
years has tended to throw doubt upon
the extent of the influence on climate and
temperative once attributed to forests.
But, on the other hand, there seems to
be no doubt that the disappearances of
bush and scrub has in many countries,
and even in New Zealand, been followed
by the failing of springs and the disap-
pearance of rivulets and streams. In the
handbook on "Tree Culture in New Zea-
land," issued by our Chief Forester, Mr
H. J. Matthews, this effect is notied as
the direct consequence of the efforts made
by our settlers to clear bush land. The
experience of every country where ob-
servations on the rainfall have been car-
ried out-St. Helna and Ascension,
Asia Minor and Switzerland, Italy and
France, California, the West Indies and
Australia-all tens in the same direc-
tion. "The countless ruins of Palestine,"
says Mr A. Page in a recent issue of "The
World's Work." "the stony hills and de-
serted vallyes, are the result of maltreat-
ment of the land that once flowed with
mild and honey. Mesopotamia, one of
the most sterile countires in the East,
was once a forested and fertile land, and
the Euphrates river is now swallowed up
in the desert. Greece shows a similar de-
cadence. Sicily, which when covered
with forests, was the granary of Rome,
is now entirely deforested, and even when
undistubred by earthquakes is a poor ag-
ricultural counry. There are parts of
Denmark, Bohemia, Hungary and Aus-
tria which in modern times have become
valueless through deforestation. The
Chinese have ruined great part of their
Empire by destroying their forests, and
they are fast becoming waste places in
which no man can live." Evidence of
this kind might be multiplied indefinite-
ly, bu this may be suffiicient to suggest
the importance and value of forests in
maintaining a country's water supply
and the danger involved in the cessation
or diminution of the streams and springs
on which its fertility and productivity
so largely depend.

But his question of the water supply
is closely connected with another and
even more improatnt aspect of deforesta-
tion. Professor Schwappach, in his text
book on "Forestry," points out that,
apart from teh fact that foresta are con-
stantly adding valuable organic matter
to the soil, they have a directly beneficial
effect upon it in other ways:-

(1) They prevent the sunlight and heat
from reaching the soil directly, and thus
searing or burning it.
(2) they break the force of the wind,
and so save loose soil from scattering
or drifting.
(3 they reduce the mechanical force of
heavy rain.
(4) They bind together and keep in its
place soil that would otehrwise be
carried away by floods.

It is on the last two of these effects
that I wish more particularly to dwell,
and I believe that evidence can be pro-
ducted on these points that will convince
any intelligent person that the destruc-