Martinsburg herald. [volume] (Martinsburg, W. Va.) 1881-1920, 1891-03-14
About wind and winds,ormz.

Wind has been yariously defined, as
air in motion, a sensible movement of
the air with reference to the earth's
surface, e!c. The word is usually APP
piled, says Prof. Guyot, to currents of
air more or less horizontal, though
vertical or slanting currents of air,
whether ascending or descending,
equally deserve the name. The hori-
Zontal component of this movement of
the mir is usually that which is specially
referred to by the term wind, but the
powerful vertical movements that take
place in tornadoe5 aud other severe
storms may also be included under the
same subject. Says one authority: In
general, wind is the result Of an
initial, local disturbance of the density
OF the atmosphere, in consequence of
which the air Is ct in motion its motion
is then modified by the resistance of
the earihs surface, and by the diurnal
rotation of the earth about its axis, and
may lie propagated into regions far dis
tant from the original seat of the dis
turbance. Some winds have, as indi-
Gated, local or temporary character,
while others are very permanent, or pre-
vail ever large areas; these latter are
genera ly spoken of us currents, as dis
tingui,hed from the local or temporary
movements which retain the designation
winds. Space forbids anything like a
full article on thi, interesting subject,
hence we must condense the points aud
give them as notes to the reader to fill
out 1t has been ascertained that, be-
tween the Iatitudes 30 degrees north
aud 30 degrees south, the lowest stratum
OF air moves westward; between these
parallels and the respective poles, the
resultant motion of the lowest stratum
If he trials LEFT bv shooting stars show
that at heights of from five to 100 miles,
great diversity of currents prevails,
but no one direction predoninates.
The most importants Of the general and
and periodical currents are the trade
winds which prevail between the
parallels 30 degrees north and 80 de-
grees south, latitude, but attain their
full breadth and force only 10 mid
ocean, and are very materially circum-
scribed near the Eastern and Western
COHtiH9HbS. Inc dutl-Urhu6S IS q term
which de3iguates the current of air that
prevails quite uniformly alb We the trade
wirds, at height of 5000 feet or more
above the surface of the earth; this cur
rent Is also known as the upper-trade,
or return-trade, and seems to be merely
the return to the temperate zones of the
air that had flowed at the surface to-
ward the equator. There are also the
monsoons, from Maylayan or Arabic
word, signifying seasonal, which COM
prise all winds that with the season
change their character from being land
winds to sea wind We hive, further,
the day breeze and the night breeze, or
the Land wind and the sea wind, which
arc less pronounced than the nlousoons;
ard there are many special winds,
which arc usually known by special
local namet When currents Of air
which are moving in difTe ent directions
meet one another, a wbir.ing motion is
impaired to the atmosphere, as the
simple Illustration of wind carrying up
dust from tie ground shows; and this
movement. on.y Oh large scale, is a
storm, aud it is often accom- panied by
rain or snow when the wiuds thus en-
counterlng each other are of different
tcmpeTatnre