Evening star., 1898-12-26
STEERING a BALLOON.
An English AerOnaut's Test of An
drec's Arctic Apparatus.
From the London Chronicle.

From the London Chronicle
For some time Mr.. Percival Spencer, the
most celebrated of aeronauts, has had it in
contemplation to test the sail and trail rope
gear used by Andree in his attempt to
effect the aerial conquest of the north pole.
The conioint system of trail rope and sail
has never yet heen practically tested to any
extent, and the idea of it is this: In free
balloon you are always in a perpetual calm,
for you travelling at the same rate as
the wind. A sail would therefore, be as
little use for directing purposes as rud-
der in a boat drifting in current without
oars or any means of propulsion. To use
your sail you must have trail rope, so
that Immediately you descend and get
certain proportion of your trail rope with
its weight on the ground, your balloon is
retarded You are not then travelling at the
same rate as the wind-i. e., you are not in
a perfect calm, and your sail can act. by d
proper manipulation of ballast you arrange
that a certain portion of your trail rope
shall be eartn-borne, and the course of the
balloon correspondngly retarded.
You have, however, no guiding power in
the trail rope and for this the sail is used.
The retardation of the balloon given by the
drag of the trail rope creates a breeze, ami
this acts on the SAIL which, by maninu-
lation of the trail rope, causes the balloon
to be slanted to the right or left of the wind
course, according to the direction in which
it is desired to diverge. The trail rope we
USED was ordinary lnree-lncn nGfnIp-lt must
be remembered that rope is measured by
its circumference-and was 800 feet in
length. The tests, therefore, required that
the balloon should be at a height of less
than 500 feet. The sail carried was
rigged, as in Andree's balloon, a spar
made fast across the equator of the ring
( that supports the car, and, stretching up
ward. it was made fast to the netting of the
balloon. 1t was of sort of duck, very
light canvas, in fact, ordinary square
sail of twelve feet weighing ten pounds
The trail rope was attached to the coi,.3E
of the ring. At each side of the spar whe-3
it crossed the ring pulley blocks were fixed,
through which guy ropes were passed and
fixed, by what appeared to be rolling
hitch" knot, to the trail rope some feet be-
low the car. To bring the gear into opera
ton, as soon as part of the trail rope is
earth-borne, you haul on one of the rores
either to right or left, and so bring your
sail surface to the wind according to The
direction in which you wish to guide your
course.
At 1:55 came down and began our trail
rope experiments. being then over Cranham
Hall. Almost Immediately we had got sorIe
hundred feet or SO of our rope earth-borne,
we found that 1t would come straight across
a field, and over four plows each with its
plcwman and pair of horses. A hail to the
men warned them to take their teams for
ward; our rope trailed safely past the ham
dies of the plows just behind them, and a
shout from the men gave us our location.
One of the prettiest sights of the trip cc
Cured in a field a little further FGur
young horses were there grazing, and their
amazenlent at the great weird snake tHat
was swiftly crossing the field was delicious
to behold A wild start and then they trot-
ted up and shifted at 1t deliberately. A
shout sent them off in a headlong gallon,
only, however. to trot back again and Won
deringly watch the rope, but this time at
a discreet distance.
At 2:1O we had rather an exciting contre-
temps We suddenly saw that our trail
rope was bound to pass over the roof of a
large house which was hid in thick trees
First resting on the trees at one side the
rope, as we crossed, dropped straight across
the roof To our delight, however the
chimney pots over which 1t trailed appeared
to suffer no damage, and in a second the
rope was again borne on the tree tops at
the other side of the house. This perhaps
may explain an Incident that happened a
few minutes later for suddenly glanciag
down we saw a burly policeman running
for all he was worth across a field after
ever though he made long run of It. and
the last we saw of him he was gazing
wrathfully up at us from the center of a
huge plowed field, evidently TOO ''pnnped"
to shout. And now word as to the result
of the trail rope experiments.
Our experiments were made at a height
of from 300 feet to 400 feet, thus lea wing
from 100 feet to 200 feet of trail rope OF, |
the ground. We found that with this lever
age we could work our sail and the balloon
to which it was fixed so that We coula
diverge a point and quarter - Eight or
left of the wind course In fact it gave us |
a range of two and a half points within 4
which we could alter the course of the BAL
loon. With the wind blowing west ty
south, our course was naturally east by |
north Compass bearings taken showed IL 1
as about half way between east by noisn