The Stourbridge Observer, Cradley Heath, Halesowen & District Chronicle.
Stourbridge, West Midlands, England, 1872-11-09 00:00:00

EXCEPTIONAL WEATHER.

The following communication, sent to The Times for
publication, will interest many Ed our readers
We are having just now what may be termed 'exceptional
weather," continued heavy falls of rain causing deluging
goods of a very destructive character. Many persons who do
not understand what is the origin of meteorological pheno-
mena inter excess of rain from very inadequate causes—as
extensive land draining, cleszing of forests by the cutting
down of timber, cultivation, d:c Works and operations of this
oh iracter do modify local climatee during ordniary seasons and
period,. Draining land, by removing stagnant surface and sub-
soil water, raises the temperature in proportion as excesieof
evaporations prevented Cetting down large forests may hove
acomplicated effect,as thick forest prevents eubsoil and surface
evaporation by shutting if the rays or the sun, but growing
timber is s very powerful evepo ator g, every pound of
woody Mire formed seve al hundreds of pounds of water
must he evaporated ; every blade of grass, while growing,
is however, also a water evaporator. Wet, is therefore, a
uecessars elem. lit to growittir vegetation, the most minute
or the meet gigantic without silt there is nu protecting
vegetation. Mate the growth of permaneet grasses impos-
sible, as beneath the c mper smoke of the Vale of Swansea,
and all vegetable soil vanishes. The wide arid deserts of the
earth become and remain deserts for lack of atmospheric
moisture and sunsoil water.
Meteorology cannot he explained briefly ; an enumeration
of the leading elements may, however, be short and simple.
The sun furnishes the heat, the salt ocean the water, and
the atmosphere the laboratory If the heat of the sun
anneally varies (as no doubt it does within certain limits)
evaporation from the ocean m set vary, arid condensation from
the atmosphere must also vary. It may he stated broadly that
fresh water, upon the surface or beneath the surface, over
the entire globe, can have no other othin thee the huge
salt ocean, which covers more than three-fifths of the earth.
Evaporation is unceasing from the equator to the poles ;
snow-capped mountains, glaciers, and icebergs are evapor-
ating, and during the deluging MOIIBOOII tropical falls of
rain there is excessive re-evaporation. Much of the water
evaporated falls over the ocean, but the land, and especially
mountain peaks and ranges, are the gigantic condensers :
here the ever.moving atmosphere precipitates any excess of
moisture it may contain in snow, hail, dew or rain. Spring,
lakes, and rivers, however gigantic, owe their orgin to the
I imperceptible lifting of water from the salt ocean in pure,
transparent vapour.
The subtle phenomena of "latent heat" in transparent
vapour need not be further touched upon, though it is this
"latent heat" which is largely concerned in, pot only the
most simple, but also in the grandest exhibitions of nature
as hail, snow, wind, thunder, lightning, dew, and rain.
Evaporation being constant, arid in area as the entire sur-
face of the earth, condensation in its most active form only
occurs on portions of the dry land, and there not
equally, but In excesses, not only in any one year, brit, as
In the day. of Joseph, in a series of years. The water eva-
porated from 10,000 square miles may be precipitated ii rain
over I,eoo square miles, so that for the time 9,000 square
inCes must be without rain. one thousand, one million, or
any imaginable area may be supposed, and the fall of rain
may in continuance be even as one huudred. one thousand,
or any other number or times in excess ; it is only required
to impress these leading facts on the memory. A wet year
over the entire surface of the earth or a dry season Is equally
impossible. If there is more heat from the sun in one year
:hen in another year, there mast be more evaporation and
more condensation; but then comparatively small areas of
the earth's outface will receive the exceeses. An excep-
tionally wet season O:Tr Europe will assuredly have, or be
contrasted by, an exceptionaily dry season over some other
Equivalent area. This is so, and most be an. Excemes in
aature beget excesses. The condensing and liberation of
latent -hez..r, works literally with steam power to cause excess
up to exhaustion.
The heavy and continued fall of rain over Italy is only ex-
ceptional as regards this season, sazli floodings have occulted
before, and will, inevitably, occur again and these facts
statesmen, engineers, agriculturalists, and others ought to
iinderttand. It is a disgrace to a G svernment to neglect
public works which would, if executed, prevent wale-spread
catastrophe, it is a disgrace to an engineer to plan and
construct emhankmeuts, viaducts, roads, and bridges, which
the first violent flood sweeps away.
excesses ought to have been provided I or, as these ex-
c./re: are part of the order of nature, and cannot be pre-
vented. I:en cannot reduce the heat of the sun, he cannot
lessen the area 0,1 the ocean, neither can he direct or modify
the wild turmoil of the atmosphere in the tornado or mon-
soon violence but he can anticipate the worst, from the
gait; and, with full knowledge of the power of the elements
own weakness, prepare and work accordingly.—l
have tbe honour to he, fic.,
RJeeltr RAWLINSON, CE., Civil Engineer.
London, Oct. It.