Roanoke daily times. (Roanoke, Va) 1886-1890, 1890-01-03
FROM HIGH TOWERS.
How they VIII no Important Assistants
in meteorological Inquiry.

London is to have larger edition Of
the Eiffel tower 1t will be 1900 feet
high, and will enable scientific men to
make important observations not posi-
bic on the earths surface.
The proposed tower would allow Of an
inquiry into tile atmospheric conditions
up to l ECO feet Instruments for meas
uring the heat of the suns rays, such as
black bulb thermometers in vacuo, and
actinometers, disposed at the top and
bottom of the tower, would also give
very interesting readings, the instru-
monts at the highest station probably
showing an excess of the suns heat over
the other, because of the atmospheric
humidity intervening between the earth's
immediate surface and an altitude Of
1900 feet.
Thermometers disposed 1T various
heights and properly screened from
radiation would show the temperature of
the atmosphere at different levels; the
air would probably be found cooler on
rising higher and higher, giving this Gu
rious rcsult-that Tie sun would be
warmer ut the top than at the bottom;
bat, in the absence Of the sun, the air
would be colder at the top. At night
the distribution of the temperature in
the atmosphere is known TO be the re-
verse of the daytime. On a flne, clear
night the temperature will be found
higher at LOCO feet than it is on the
earth, while On Il cloudy night it will be
much ,ha same 10 both stations; but we
have much To learn of the laws of ter
rcstial radiation, and the proposed tower
would be very useful in that respect.
or course an observer would not be
expected to race day and night up and
down tower 1900 feet high, to make
observations and read thermometers;
this would be too great, and indeed an
unnecessary devotion to science. The
whole thing can be done from below in a
comfortable building By means Of Sic
mems electric thermometers. Such an
instrument has been used for some time,
and is now atwork at the Lincoln cathc-
Gral, giving correct thermometer read
ing on the earths surface from height
of 30 feet. Besides observations for
temperature at various attitudes, the
state Of humidity OF the atmosphere, a
condition greatly concerned i'll the forma-
ton of fogs, could be readily examined,
dry and wet bulb thermometers disposed
at various heights and in electrical con-
nection with the station below would
yield interesting observations, and assist
materially in conjunction with the ba-
rometcv in forecastins the weather.
The force and direction of the winds
at various attitudes are subjects for me-
teorological inquiry of much interest
and Importance; there are eddies in the
atmosphere, spiral and upward currents,
of which little is known, and tower
such as that now contemplated would
allow of very interesting observations to
be made on winds. We may also ven
turc to suggest that theinformation thus
obtained would have az important prac-
teal bearing in an engineering point of
view, rs showing the strength of the
wind buildings may have to withstand
at great heights. The measurement Of
rainfall, made simultaneously at 1900
feet and on the ground, would add to our
knowledge of the laws of rainfall; i!
would be found that less rain falls at the
top than at the bottom. The connection
of this phenomenon with atmospheric
humidity and temperature would be
very interesting to investigate.
Finally, earth tremors, the forerun-
ncrs of earthquake, would be felt at the
summit OF high tower much more
readily than in contact with the earth,
and earthquakes might be expected to
produce greatly magnilied effects at such
an elevation; hence seismometer
would find fitting place at the top Of
the proposed building. y great deal
might be added on this subject. We have
not touched on the astronomical uses of
very high tower from the greater clear
ness of the atmosphere at such an alti-
tude. There are also other points Of physi-
illogical interest that could have been
dwelt upon, such as the influence Of an
altitude of / 200 feet on respiration, or
on the nervous system. 1t might be re-
marked that there would bc little fear of
feeling giddy when looking down from a
tower of such height, although the view
over q precipice of 1900 feet would not
be unlikely TO produce q most unpleas-
ant sensation.-British Medical Journal.