The prison mirror. [volume] (Stillwater, Minn.) 1887-1894, 1890-07-17
Electrical. Scienec.
FIFTH PAPER.


Galvani having advanced his theory of
animal electricity. found opposed to him
the Italian Volta (1745- 1920, his objection
to Galvani's views being taken on the
ground that electricity was produced from
the contact of two different metals. and
that the frogs legs were but moist con-
ductOr, and as such were no better than a
wet rag" To prove this he constructed
what is known as the -''Voltaic pile" This
was constructed by taking silver coins-as
silver gives better results than copper-and
| on the silver disk he placed one of zinc. and
ON this disk of mOistened leather or paper,
and so on alternately until he had
several dozens of each kind. placed one
above the other. At the extremities of the
pile he connected two wires, between the
ends of'whieh, when brought close together,
electric sparks passed, and by touching
with the fingers at the same time the upper
and lower ends of the pile an electric shock
was received. Apparently Volta had no
idea o. the many uses to which this appa-
ratus could be put, having gone no further
than to show that this apparatus was proof
conclusive in favor of the contact theory, as
advanced by him: that the moistened disks
of leather only serve to connect the several
metallic disks and carry the current in one
direction he fully believed. although hav-
ing found that when the disks were moist
ened with a solution of acid, the effect was
more powerful, the chemical changes when
acids were used was passed over without in
fiprnf T,,k hi ofr,ov
germ of all the electric batteries con-
structed since his time. Volta afterwards
modified his apparatus. He took several
glass vessels filled with saline solution.
into each of which he introduced a plate of
copper and one of zinc, connecting them
with wires, one end of which were fastened
to the copper, the other end to the zinc
plate in the adjoining vessel. This battery
was known as the ''crOwn of cups" and
forms strong battery. Following this dis
cOvery numerous batteries were constructed.
probably the best for general use. where
high degree of intensity is desired, would be
Bunsen's battery. First obtain glass or
porcelain vessel and into this pour guam
tity of diluted sulphuric acid, then bend
piece of amalgamated plate zinc into cir
cular form, making hollow cylinder; with
wire fastened to the top, place this in the
vessel containing the acid. then take an
earthenware vessel, sufficiently small to be
placed inside the zinc and partially filled with
strong nitric acid. Next insert into this YES.
sci containing the nitric acid, solid cyln-
der of hard gas etOrt carbon. to the top of
which attach wire. A single cell thus
constructed is capable of generating large
quantity of electricity. To increase the in
tensty connect several such cells by joining
zinc to carbon, taking care on completing
the battery to have one wire leading from
the carbon, the other from the zinc, in order
to complete the circuit
The opening years of the present century
mark new era in the science of electricity.
Its forces were gradually determined. men
of science in all countries were awakening
to the immense possibilities Of this new and
wonderful force. Have their widest dreams
not been surpassed? No human mind ninety
years ago could conceive that the wonderful
though apparently insignificant force would
ever be developed to such an extent as to
replace fuel, light and the use of animal To-
connective powers. Different authors agree
in the statement that the reports made by
different students of this science and read
before the Royal Society of London during
a period of about fifteen years, amounted to
nearly three thousand. Among these re-
ports were some from such men as Humph-
rey Davy. WOllastOn Cruikshank, Brazel-
ius. PeypO, PriestIy, Blot. Guy Lussac. De
la Rive. Faraday, Sir William Thomson,
DR.. Hare. of Philadelphia and scores Of
others too numerous to mention.
VOlta's discovery and construction of the
battery was the incentive needed for those
men to study and develop this wonderful
and attractive I'm double sense) science.
LEONARDUS.
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Carl Pretzel's Philosophy.
Der race course of sin und vice dond vas run