Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1886-11-11
TnE FLEcTRIc ROAM YoIrA.
Its Construction and Its Voyage from Dover to
Calais.


Calais.
London Times.
The latest example of an electric DO at
prior to the Volta is afforded by a steel
launch built by Messrs. Yarrow g. Co.
during the present year for the torpedo
service in the Italian navy. The boat is
SO feet long by 6 feet inches beam, and
is propelled by a screw driven by du-
pick ReckenZaun motor She made on
the measured mile 8.43 miles per hour,
and is now in regular service at S pezzia.
In each case the electric current is stored
in a battery composed OF the Electric
Power and Storage Companys cells.
The latest outcome of electrical science
in the present direction is the Volta,
which is steel built, measures 81 feet long
by 6 feet 10 inches beam, and is fitted
with battery OF sixty-one cells made by
the electric Power and Storage Company
and dublex Reckenzaun electric motor
that is, two motors carried on one driving
shaft. BY means of this motor the speed
can be varied without affecting the accu-
mulators, three speeds being obtained
from it, namely, slow, medium, and fast.
For the slow speed the motors are coup
led in series, for the medium speed one
motor only is used, while for the maxium
speed the two motors are used in parallel
that is, they are both worked at high
pressure. Another important feature is
that all these speeds can be obtained and
the vessel started and stopped by means
of one switch only, having one handle
thus reducing the control of the
speed of the boat to the Sim-
/ plest terms. There is a separate switch
/ for reversing the motion of the motors
| from ahead to astern vice versa, and this
is done by simply reversing the current
through the armature without interfering
with the field magnets and requiring only
two brushes to effect the operation, which
brushes are never moved. The motors,
which are placed well aft, directly over
the keel, measure together feet 10 inch
es long by foot inches wide and 12ll
inches high over all. They weigh $50
pounds and develop maximum of 16-
horse power on the brake. The Volta is
propelled by three bladed screw 20
inches in diameter and 11-inch pitch,
cospled direct to the motor shaft The
propelling machinery makes about 600
revolutions per minute at the slow speed
and about 1000 revolutions per minute at
full speed. The storage cells weigh about
two tons and are arranged along the keel
OF the vessel beneath a wood ducking.
The battery of the Volta was charged
by dynamo on shore at Dover, the ell
ectro-motive force at starting being 100
volts at IS amperes. She passed the
pierhead at Dover at l0;41 It. IN. and made
the pieaheGi at Calais at 2:32 p, M, the
run having thGs occupied three hours
ana ffty-one minutes. She carried on
board General Brine, Il. +. Mr.. Reckon
zaun, Mr.. Stephens, and several scientific
gentleman, making with the crew, ten
persons in ALL The Volta did not take
the direct route having gone somewhat
of her course when nearing the French
coast. She was propelled at slow
speed GOO revolutions per minute), III
order to economic the current and IN
sure it's lasting the whole run, speed not
being so much an objects as to demon
strate the practicability of a vessel max
ing such voyage by electricity. On
testing the battery at Calais no difference
what ever was found, the cells still show
ing p amperes, as at starting. The
progress of the boat through the water
was very smooth and noiseless
SO much so that as stated by US
yesterday, sleeping gannet was captur
Ell by MAUI rs tue DOaN was passing IT,
and was conveyed back TO Dover. On the
return journey, which was run at low
speed, Calais pierhea6 vas passed at 3;14
p. m, and Dover pierhead made at 1857
p. m, being hours % minutes for the
run--or a total of hours ii minutes en-
ployed in travelling the double journey
exclusive of the stoppage at Calais. The
current remained constant at % amperes
up to p. m, but at six p. m, 1t was
found to have dropped to 20, another am
pere being lost before Dover was reach
ed, An excellent margin of power, how
ever, still remained, and the last half mile
was run at the high speed, the motors and
screw making 600 revolutions per min
ute The practicability of electrical pro
pulsiou was thss successfully demonstrat-
ed, and the way doubtless paved for the
further application of the principle i'll the
di rection indicated by the class of craft
TO which it had previously been applied.