||But Bose was only
one of several German scientists who were making elaborate experiments.
While Bose was constructing and experimenting with his huge machine, another
German, Christian Friedrich Ludolff, demonstrated that electric sparks
are actual fire - a fact long suspected but hitherto unproved. Ludolff's
discovery, as it chanced, was made in the lecture-hall of the reorganized
Academy of Sciences at Berlin, before an audience of scientists and great
personages, at the opening lecture in 1744.
In the course of this lecture on electricity,
during which some of the well-known manifestations of electricity were
being shown, it occurred to Ludolff to attempt to ignite some inflammable
fluid by projecting an electric spark upon its surface with a glass rod.
This idea was suggested to him while performing the familiar experiment
of producing a spark on the surface of a bowl of water by touching it with
a charged glass rod. He announced to his audience the experiment he was
about to attempt, and having warmed a spoonful of sulphuric ether, he touched
its surface with the glass rod, causing it to burst into flame. This experiment
left no room for doubt that the electric spark was actual fire.
As soon as this experiment of Ludolff's
was made known to Bose, he immediately claimed that he had previously made
similar demonstrations on various inflammable substances, both liquid and
solid; and it seems highly probable that he had done so, as he was constantly
experimenting with the sparks, and must almost certainly have set certain
substances ablaze by accident, if not by intent. At all events, he carried
on a series of experiments along this line to good purpose, finally succeeding
in exploding gun-powder, and so making the first forerunner of the electric
fuses now so universally used in blasting, firing cannon, and other similar
purposes. It was Bose also who, observing some of the peculiar manifestations
in electrified tubes, and noticing their resemblance to "northern lights,"
was one of the first, if not the first, to suggest that the aurora borealis
is of electric origin.
These spectacular demonstrations had the
effect of calling public attention to the fact that electricity is a most
wonderful and mysterious thing, to say the least, and kept both scientists
and laymen agog with expectancy. Bose himself was aflame with excitement,
and so determined in his efforts to produce still stronger electric currents,
that he sacrificed the tube of his twenty-foot telescope for the construction
of a mammoth electrical machine. With this great machine a discharge of
electricity was generated powerful enough to wound the skin when it happened
to strike it.
Until this time electricity had been little
more than a plaything of the scientists - or, at least, no practical use
had been made of it. As it was a practising physician, Gilbert, who first
laid the foundation for experimenting with the new substance, so again
it was a medical man who first attempted to put it to practical use, and
that in the field of his profession. Gottlieb Kruger, a professor of medicine
at Halle in 1743, suggested that electricity might be of use in some branches
of medicine; and the year following Christian Gottlieb Kratzenstein made
a first experiment to determine the effects of electricity upon the body.
He found that "the action of the heart was accelerated, the circulation
increased, and that muscles were made to contract by the discharge": and
he began at once administering electricity in the treatment of certain
diseases. He found that it acted beneficially in rheumatic affections,
and that it was particularly useful in certain nervous diseases, such as
palsies. This was over a century ago, and to-day about the most important
use made of the particular kind of electricity with which he experimented
(the static, or frictional) is for the treatment of diseases affecting
the nervous system.
By the middle of the century a perfect
mania for making electrical machines had spread over Europe, and the whirling,
hand-rubbed globes were gradually replaced by great cylinders rubbed by
woollen cloths or pads, and generating an "enormous power of electricity."
These cylinders were run by belts and foot-treadles, and gave a more powerful,
constant, and satisfactory current than known heretofore. While making
experiments with one of these machines, Johann Heinrichs Winkler attempted
to measure the speed at which electricity travels. To do this he extended
a cord suspended on silk threads, with the end attached to the machine
and the end which was to attract the bits of gold-leaf near enough together
so that the operator could watch and measure the interval of time that
elapsed between the starting of the current along the cord and its attracting
the gold-leaf. The length of the cord used in this experiment was only
a little over a hundred feet, and this was, of course, entirely inadequate,
the current travelling that space apparently instantaneously.
The improved method of generating electricity
that had come into general use made several of the scientists again turn
their attention more particularly to attempt putting it to some practical
account. They were stimulated to these efforts by the constant reproaches
that were beginning to be heard on all sides that electricity was merely
a "philosopher's plaything." One of the first to succeed in inventing something
that approached a practical mechanical contrivance was Andrew Gordon, a
Scotch Benedictine monk. He invented an electric bell which would ring
automatically, and a little "motor," if it may be so called. And while
neither of these inventions were of any practical importance in themselves,
they were attempts in the right direction, and were the first ancestors
of modern electric bells and motors, although the principle upon which
they worked was entirely different from modern electrical machines. The
motor was simply a wheel with several protruding metal points around its
rim. These points were arranged to receive an electrical discharge from
a frictional machine, the discharge causing the wheel to rotate. There
was very little force given to this rotation, however, not enough, in fact,
to make it possible to more than barely turn the wheel itself. Two more
great discoveries, galvanism and electro-magnetic induction, were necessary
before the practical motor became possible.
The sober Gordon had a taste for the spectacular
almost equal to that of Bose. It was he who ignited a bowl of alcohol by
turning a stream of electrified water upon it, thus presenting the seeming
paradox of fire produced by a stream of water. Gordon also demonstrated
the power of the electrical discharge by killing small birds and animals
at a distance of two hundred ells, the electricity being conveyed that
distance through small wires.