The Columbian. [volume] (Bloomsburg, Pa.) 1866-1910, 1894-01-19
TEN MILES ABOVE EARTH.
Interesting Experiments mt the Highest
Point q Bnloon Ever Reached.


One of the most interesting expert
mentS with balloons that has ever bc,u
undertaken was that of Mcssrs. Hcr.
mite and Besancon at Paris-vaugirarl
They succeeded In sending balluuL
to the unprecedented elevation of IT,,
900 metres, or about 10 miles There
were no people In the balloon, but II
carried variety of self-registering In
struments designed TO record the TEN.
pcraturc, the atmospheric pressure,
etc. The little balloon was started on
its lofty trip about noon, when the air
was remarkably still and clear. 1t
rose rapidly. and In three quarters of
an hour had attained an elevation of
10 miles, at which height 1t remained
for several hours.
1t was there subjected to an atmos-
pherlc pressure only about one-eighth
us great as that at the surface of the
earth, and NJ. Hermite explains its
floating for so long a time at con-
slant height by supposing that the tenn
perature does not vary sensibly with
the elevation of the floating body after
the latter has attained an altitude
where seven-eighths of the atmospher-
ic pressure is lacking and where there
remains no trace Of water vapor.
But towards o'clock, when, with
the decline Of day, the temperature be-
gan rapidly to fall, the balloon started
back towards the earth, arriving with
gentle motion which did not disturb
the instruments Il carried, Mt 7:11 at
Chanvres, near -Vaugirard, from
which 1t had started.
The balloon was visible with n tele-
scope during the entire time 1t shone
like the planet Venus seen by day
BY means Of n micrometer attached to
an astronomical telescope the apparent
diameter of the balloon could easily
have been measured, and this would
have furnished means of calculating
its altitude independent of the record
OF the barometer which il carried.
The barometer and thermometer were
furnished with automatic pens driven
by clockwork, by means of which d,a-
grams of the changes of pressure and
temperature that the balloon expert
enced We're obtained. At the height
OF about 7A miles the Thermometer
marked n temperature of 80 degrees
Fahrenheit below zero. Then the ink
in the registering pens of both the
thermometer and the barometer be-
came frozen and the records were in
terrupted.
But, as the balloon continued to rise,
the ink thawed again. and at The ten
mile level the automatic records were
renewed. The temperature registered
there was only about degrees below
zero. The increase of temperature Is
ascribed to the effect of the unclouded
sun heating the air In the basket that
contained the instruments. The low
est record of the barometer was 103
millimetres, or trife more than four
inches.
NJ. Hermlte calls attention to the
fact that the density of the air Mt the
height of ten miles, where the balloon
remained during most OF the afternoon,
Is less than that existing upon the
plains of the moon, on the assumption
that the atmospheric density on the
moon is proportional to the force Of
gravity at the surface Of that orb.
If this is correct, then the instru-
ments would have behaved about the
same IL M. Hermite had been able to
place them on the moon as they did
when he sent them only ten miles
above the earth.-Youth's Companion.