The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1896-06-09

found that the relative atmospheric hu-
Nudity decreased from 100 per cent. at
5000 feet altitude, to per cent. at 1880
feet.
1t is not necessary, however, that aeor-
nauts should risk their lives in extreme
ly high ascensions to ascertain these
facts.as was done by DR.. Berson and 9TH
ers, when they can be ascertnined with
sufficient accuracy by means Of captive
balloons carrying self-registering instru-
ments. Such balloons can ascend to
heights where it would be impossible for
an aeronaut to live, even with oxygen
inhalation; SO that it is not impossible
that the atmospheric conditions pre-
vailing at an altitude Of even ten miles
or more may yet be asoertained in this
way.
Captive balloons have various other
important uses. They are employed for
both military and naval observations, ono
object Of which is to locate and recon-
noitre the onemy's position in war.
which can be thus asoertained even when
far below the horizon of an observer at
the mast head of ship, or on the watch
tower OF fort.
Another important use to which they
are now applied is to convey the life
line from a wrecked ship to the shore;
several hundred small balloons having
recently been ordered by the United
States life saving service for this pur-
pose. A ship provided with one OF NOR
OF these balloons. if wrecked on 3 lee
shore, can easily send line on shore by
the balloon, when it might be impossible
to shoot one by mortar from the shore to
the ship against the wind. Or line can
be sont from the shore to the ship in the
same way. il a position can be found
where the wind is favorable.
While the employment of the balloon
for exploration, for war, and for other
important purposes indicated in this ar
ticle is already we'll assured, its limited
capacity, comparatively large cost, and
lack OF experience in it's management
render its use for commercial purposes.
as the carrying of passengers or freight,
practically impossible under present
conditions. There is. however, one way
which has not been indicated in which
1t may possibly Re used for the transpor-
tatlon OF passengers and freight, if tinan-
clal success In competition with existing
means of transportation can be assured.
Thls is by the construction of suitable
electric line, and the use in connect on
with it of captive balloon
Such a line conld be constructed with
substantial poles of steel or wood, locat-
ed at short distances apart, and carrying
on suitable brackets double line, con-
sisting either of stout wire ca bles or
light rails, similar to those used as con-
duotors on elevated electric railroads. the
two branches Of the limo being insulated
from each other, SO as 20 make COM
pleted electric circuit. Over this line
navigable balloons, of the elongated
type, could be propelled by electric mo-
tors, obtaining their currents from the |
line in practically tho same manner as
they arc obtained by electric cars, and |
connected with it by stout flexible con-
ductors, terminating either in trolley
wheels or sliding shoes, by which the
pa.iouH shoulU DC held to the track with
sufficient force to resist strong wind
and the comparatively slight upward
pressure.
As the lpropelling apparatus would
consist only OF the electric motor and |
screw, motor Of sufficient power to I
produce q high speed could be used
without absorbing SO much of the lift
ing power by it's weight as to reduce
the load of passengers and freight below
profitable limits. And with proper
steering and propulsion. the strain on. q
we'll. constructed track by tho force Of the I
wind against the balloon would not be
sufficient to disturb it or endanger the
balloon, especially as the sailing altitude
need BE- only few feet above the track,
just sufficient to clear all distractions.
An lnter-urban passenger line of this