The Iola register., 1881-10-14
Electrical Cafiosities at Tie Paris Ex.
hihition.

Electrical Cariesities at Tie Paris Ex.
hibition.
Ever since NJ. Gramme introduced
his beautiful machine for generating
the electric current, his principle has
been adopted in host of other inven-
tioDs. Shortly afterward new value of
the machine was found. we'll remem-
Der, iT 1875, returning from a prolonged
absence from England. had occasion
to write to the late Professor Clerk
Maxwell. and incidentally asked him
what was the greatest discovery of late
years. He replied that, in his opinion,
the greatest discovery was '.that q
Gramme machine could be reversed
:, e., that when current was passed
through the machine it might be used
to drive machinery. The belief of the
Professor was shared by many others.
and hundreds of people have been since
then engaged in applying this new
means of transmitting power to divers
purposes. The Electrical Exhibition
contains large number of these, many
of which can even now be seen in &C
tion. but complete notion of these ap-
plications cannot be gained until the
steam-engines, the source of nearly all
the electricity to be used in the exhibi-
ton, are in q more advanced state.
will, however attempt very shortly to
give some idea of the most interesting
examples in this department.
A great deal of popular curiosity
will. doubtless, be excited By two thor
oughly French toys on q large scale,
both made by M. Trouve. The first is
the electrical boat, which is full-sized
boat for three people, having attached
to the near end of the rudder q screw
driven by a small electro-motor. The
screw passes through q void space in
the rudder. The motor is fed by three
large bichromate oells. The mode of
attachment of the screw causes it to as
sist the rudder in turning the boat, so
that NJ. Trouve has been easily able to
float round the artificial pond which
surrounds the lighthouse in the center
of the building, and to pass under the
picturesque arches by which it is
spanned at the rate of about a mile an
hour.
The other is the electrically propelled
balloon of M. Tissandier. 1t is an
elongated balloon, three metres long
and one and third in diameter. It is
filled with hydrogen, and has a screw at
the rear, driven by an electro-motor,
designed by M. Trouve. 1t can also
carry a couple of the secondary cells of
M. Plante. A wire is suspended across
the building from one gallery to the
other. and the balloon rises above this
wire and travels along it when the cur
rent passes. A fin placed in front pre-
vents it from swaying. But the motion
is very slow, and at present the machine
is little more than an electrical toy.
Still more interest will, however, be
excited by the tramway car driven by
electricity, the invention of Messrs.
Siemens. In this tram car, which runs
from wooden station on the Place dc
la Concorde into the exhibition, the
current is generated by a powerful
dynamo machine within the building.
1t is then carried by wire mounted on
strong posts, from which it is tapped
by carriers on the car, whence it de- |
scends to beneath the centre of the car.
Here the current, passing through a
dynamo machine, sets it in rotation. and |
by a chain connection this machine is |
geared to the axles of the wheels. The |
velocity of rotation is reduced to one
third by this gearing. The chain con-
nections are all on one side in the case
of both axles. There is also an arrange |
ment supplied for taking the current
directly from the rails, but it must be |
very rarely that such means could be |
utilized on an ordinary tramway, and at |
present it is discarded. The appear
ance of the car is very handsome, and
shows few external signs of the power |
which may be generated within it. Such |
car might be fitted with the secondary |
batteries of NJ. Faure, which might be |
placed under the seats. The car would |
be then self contained, and there would |
be no necessity for having either the !
aerial wire or the conduction through |
the rails. Such q self-contained car was |
actually constructed and tried in Paris |
some months ago, but serious difficult
ties were then encountered, which,
however, I have reason to believe will |
soon be overcome, and then we shall |
have an opportunity of seeing a car
running on q tramway and carrying its
own electrical store of energy.
In the electric brake of M. Achard.
applied to railway carriages, there are
upon the axle of each pair of wheels
two rings of iron, about eight inches in
diameter and two INCHES wide. Besides
this there is q second and independent
axle with two rings, one foot in dame
ter, facing the rings on the wheel axle.
These rings, however, are the two ex-
tremities Of a powerful electro-magnet,
which can be excited by q coil of wire,
the ends of which can be con.