March 1944 Radio-Craft
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Craft,
published 1929 - 1953. All copyrights are hereby acknowledged.
It was a big deal in 1944 when
Austrian physicist Dr. Felix Ehrenhaft announced that he had discovered "magnetic
charges," aka magnetic monopoles. He claimed based on numerous kinds of experiments
that a reversible "magnetic current" existed around current-carrying conductors.
It seems based on my reading of this Radio-Craft article that he believed
there existed mono-magnetic particles of some sort analogous to electrons and protons.
Later experiments seems to indicate that high intensity light beams could also produce
evidence of magnetic currents. Dr. Ehrenhaft widely promoted his conclusions
and invited doubters to examine his apparatus. Based on some Web searches on the
topic, independent researchers were not able to reproduce his findings, so his work
eventually faded into the background. Some credit his experiments with light for
demonstrating the particle nature of light's ability to accelerate masses. The most
profound implication of proving the existence of magnetic monopoles would be nullification
of Maxwell's equation stating that the surface integral for a magnetic field about
an enclosed area has to equal zero, precluding the existence of magnetic monopoles
(aka Gauss' law for magnetism).
Some theories in astrophysics, in order explain observed phenomena, depend upon
monopoles, so maybe the arguement is not yet settled.
The Big News - Pure
Magnetic Current - Discovery of the Age?
Dr. Felix Ehrenhaft, looking over some photos of recent experiments
with magnetic current.
By Fred Shunaman
Electrical science may well be on the verge of a new era; an age in which magnetism
will duplicate or exceed the advances of current electricity. The action of magnetic
particles in a strong field, movement of electrically-charged bubbles of gas spirally
around a magnetic field set up in a liquid, and above all, the decomposition of
water by magnetism, prove that some new thing has been discovered. How important
such discoveries are, and what their effects may be, only the future can tell.
The greatest advance in science since Oersted discovered that electricity and
magnetism are interrelated, may well have been heralded by Dr. Felix Ehrenhaft,
when he announced at a recent meeting of the American Physical Society that he had
proved experimentally the existence of magnetic current.
Electrically-charged gas bubbles in a liquid between the poles
of a magnet, move in a way similar to magnetic "lines of force." World-Wide Photos
Magnetism has always been the mysterious twin sister of electricity. It is known
that all electric current is invariably accompanied by a magnetic field, and that
electricity can be produced with the help of magnetism - as in the ordinary dynamo.
Yet practically nothing is known of the nature of magnetism itself.
Our present concepts on magnetism, as Dr. Ehrenhaft pointed out to the Society,
are based on experiments which probably originated with the ancient Chinese, and
were formulated for the modern world by the philosopher Peregrinus in 1269. Peregrinus
found that a magnet floating on water directs itself in a North-South direction,
but does not move, once it has assumed its North-South position. From this arose
the theory that magnetism has direction, but no motion.
Ehrenhaft, like Peregrinus, makes his experiments with magnets, but uses sub-microscopic
particles of iron, nickel, antimony, manganese or chromium, which, in the form of
powder, are inserted between the plates of a "magnetic condenser." (See Fig. 2.)
This condenser is a gap between the ends of two iron rods 8 millimeters in diameter.
The gap is 2 millimeters wide. Spools of wire are placed around the rods, permitting
them to be strongly magnetized in either direction. Thus the field in the magnetic
gap can be changed at will. The poles can also be connected to a source of D.C.,
and a voltage applied in the manner of an ordinary electric condenser. Electrostatic
or magnetic fields, or both together, can thereby be set up across the gap.
When a minute amount of the finely powdered metals mentioned above are placed
in the exact center of the lower electrode and the magnetic field applied, some
of these particles move toward the upper plate, while others remain at rest. If
the small metal dust particles are suspended in the air between the two faces of
the condenser, application of a magnetic field will cause some of them to move toward
the North face, others toward the South face.
The obvious conclusion is that these particles must be magnetically charged,
some with North and some with South magnetism. To persons who have been brought
up in the orthodox theory, this is hard to believe, We have been taught that if
an ordinary bar magnet is broken, each of the broken pieces will be a perfect magnet,
with its own North and South pole. (Fig. 3.) This is known as Maxwell's experiment,
and from it he concluded that if the magnet were still further broken, a whole series
of smaller and smaller magnets would be formed, and that each of these would have
its North and South pole, even if the whole magnet consisted of only one molecule
Fig. 1 - This experiment convinced Peregrinus that magnetism
had no tendency to flow, and fixed our ideas on the subject for 800 years.
Fig. 2 - The Ehrenhaft condenser. Magnetic or electric fields
may exist between its faces.
Fig. 3 - Maxwell's experiment. If an ordinary magnet is broken
in two each half is a magnet. This caused the belief that unipolar magnets cannot
Fig. 4 - Small electrically charged particles revolve around
a magnetic field as do "lines of force" around a wire carrying electricity.
Fig. 5 - Left: Ordinary electrolysis of water. Center: Bubbles
of hydrogen rising from both ends of the iron rod. Right: When magnetized, both
oxygen and hydrogen me from the poles.
Dr. Ehrenhaft believes that his experimental work proves that such is not the
case - that small particles may have unit polarity - may be magnetically charged
either North or South. If, in the condenser experiment, each of the microscopic
bits of magnetic dust had been a true magnet, complete with North and South poles,
they should have aligned themselves with the magnetic field, but certainly should
not have moved away from the pole on which they were resting. It is hard to explain
that by any other theory than that of the unipolar magnetic particle, a pure North
pole or one with South polarity only.
Effects in Liquids
Another striking example of the magnetic current is the movement, under the influence
of a magnetic field, of small particles of such metal as nickel in liquids. The
Ehrenhaft condenser, submerged in liquid, has the same effect on these small particles
that it has in air. Furthermore, on reaching one or the other of the poles, the
magnetic particles are deposited in a manner similar to that of electroplating.
To avoid possible electric effects, the poles of the magnet were electrically short-circuited
during this experiment. The result might be called "magnetoplating," rather than
If small particles are subjected to a strong electric charge while moving in
the magnetic field, their course becomes a spiral. They circulate around the magnetic
field, much as magnetic "lines of force" are supposed to revolve around a conductor
carrying electric current. See Fig. 4. Says Ehrenhaft, "In the same way the constant
electric current is surrounded by magnetic force lines closed in circles, the constant
magnetic current is surrounded by electric force lines closed in circles."
"Magnetolysis" of Water
A further experiment produces effects not previously discovered in the whole
his-tory of magnetism. The ends of a horse-shoe shaped electromagnet of plain, Swedish
iron were inserted into acidulated water. Chemical action released bubbles of hydrogen.
The iron was then magnetized, and instead of pure hydrogen, the gasses released
contained from 2 to 12% of oxygen. Fig. 5.
The water is actually decomposed by the magnet, as it can be decomposed' by an
electric current. While oxygen is released from both ends of the magnet, the larger
amount comes from the North pole.
The same experiment, repeated with a permanent magnet, resulted in a weakening
of the magnet by about 15% over a 24-hour period. This is very significant. If decomposing
water reduces the strength of a magnet, it is only reasonable to suppose that the
magnetic must be the cause of such decomposition.
A further point adduced in favor of the new theory of magnetism is that it is
possible to magnetize sub-microscopic particles with light or friction. Every experimenter
knows how simple it is to produce a unipolar electric charge on such a body as a
piece of glass, paper or hard rubber. Particles placed between the plates of the
Ehrenhaft condenser, if irradiated with light, begin to move toward one pole or
Is the Problem Cracked?
If the experiments just described have been correctly observed and interpreted,
magnetism is shown to have many of the attributes formerly supposed to belong- exclusively
to electricity. Small particles may be "charged" to a single polarity, North or
South. They may be thus charged by some outside influence such as light. Unit poles
placed in a magnetic field tend to move toward the pole of opposite magnetic polarity,
and electrostatic charges revolve in closed circles around the "magnetic current,"
as do magnetic "lines of force" (charges?) around an electric current.
Our preservation of an almost complete ignorance of magnetism through all the
startling advances in current electricity and electronics is one of the great marvels
of modern science. It would not be surprising if some one should at last crack this
problem. Dr. Ehrenhaft believes that he has done so, and has proposed experimental
proof that "Electricity and magnetism are an indivisible pair. The unification of
the field theory has been indicated in an experimental way, and electricity and
magnetism may have to be expressed in the future by one symbol only."
Posted December 14, 2020