Rock Island Argus. (Rock Island, Ill.) 1893-1920, 1904-08-16

1 a Stl4tS VI CAltl WIN NV cNAi
| looms to investigate conditions in the
upper air will be begun at the worlds
| fair under the direction of the depart
ment of the liberal arts. 1t is eX-
pected that this will prove to be one
of the most interesting of the scien-
ltific exhibits at the fair, and also it
will be a most valuable means OF adj
vertising.
An appropriation of $4,000 has been
made by the exposition company TO
carry on these experiments, the first
attempt on this continent to explore
the upper parts of the atmosphere by
means of free balloons. They will be
in charge of A. Lawrence ROtch. direc-
tor of the Blue Hill Meteorological
observatory in Massachusetts. who
first made use of the kites in the eX-
plOratiOn of the air. These kite ObSer-
vatiOns are now carried on by him each
month at Blue Hills, and similar kites
are extensively used for the same pUr-
pose in Germany and other European
countries.
In many ways. however. free bal
looms are preferable to kites for car
:
and it remained for Col. j. ~ OCker-
son, chief of the department of liber-
al arts, to arrange for the first use
of these balloons in America, although
their use is not uncommon in Germany
and Franco. Germany leads in the
manufacture of such balloons. and the
ones to be used at the exposition have
been imported from that country. Bal
looms similar to the ones that Will be
used are now on exhibition, with other
devices for the study of the upper air,
in the palace of education and So
cial economy. where the department
of liberal arts has installed many of
its German exhibits.
The balloons which will be used at
st. Louis are now at Blue Hills They
are spherical with a diameter of
about six feet when inflated, and are
made of soft rubber, something like
that used for dentists dams, but finer
and stronger. They are floated by be
ing filled with hydrogen. The great
supply of this gas which will be need !
ed at st. Louis for the balloon com |
petitions makes the plan for the air |
exposition experiments practicable and |
not expensive. Over the balloon is |
fitted a parachute, from which small !
cords lead through loops in the sides |
of the balloon to the basket carrying |
the instruments. about ten feet below |
the gas bag. The instruments weigh |
about pound, and the balloon is
filled with gas so that it will just |
rise from the ground.
A. h., I,J ri -,
less dense and the hydrogen expands. |
the balloon to rise faster. The |
heat of the sun, which is greater in the |
upper air than on the earth, also ex-
pands the gas and still further in
creases the speed. So the balloon |
goes up until the increasing pressure |
of the gas bursts the rubber bag, |
which falls into the net of strings The |
already spread, catches the |
air and the apparatus descends gently |
to the ground, usually without any
damage to the instruments. Nice |
of the expansion of hydro
gen. the strength of the rubber and the |
density of the air at various heights |
make it possible to have the balloons |
burst very nearly at determined |
height. They have pccn sent as high |
as eighteen miles. but these used at
the exposition will be planned to burst
1T Il height of about ten miles. SO that
the results may be comparable with
those obtained under the same con
ditiOns in Europe
The instruments in the little basket
include an aneroid barometer and a
thermometer. and sometimes a hygero-
meter for measuring moisture of the
air. All three instruments make a sim
lltancOus record upon moving cylin-
i"". The cylinder is covered with lamp
lack, treated with "tonsol," and the
l"n making the record uses a solution
If saltpctrC. which gives red line not
affected by water or handling. The
balloon reaches its top height in
about an hour and takes two hours
% get back to earth. The recording
line made during the ascent. which is
much shorter. is the one used because
he instruments are less affected by
he heat of the sun. Errors from this
cause are often avoided by sending
up the balloons an hour before sun
rise, and descent occurring in daylight.
when they may be more easily found
md returned to the sending station
1t the exposition it is proposed to
make the first ascent during August
and to send up two or three of these
balloons each week, until October.
when there will be a congress of aero
laUtS at the fair and the asconts NAV
De more frequent. Rewards will be
offered for finding and returning the
1araChutCS and inst rIImautS and tboco |
Will serve to keep the people living
within hundred miles OF ST. Louis
N the lookout for the ballons and will
also be an excellent means of adver-
Using the fair, as the time of the as
'ents will be widely published
An ingenious device is used in
france for keeping track of these free
balloons. or "ballons sondes,' as the
french call them. and this probably
will be used in the American expert