April 30: Electron
In 1897, at the Royal Institution Friday Evening Discourse, Joseph
John Thomson (1856-1940) first announced the existence of electrons
(as they are now named). Thomson told his audience that earlier
in the year, he had made a surprising discovery. He had found
a particle of matter a thousand times smaller than the atom. He
called it a corpuscle, meaning "small body." Although
Thomson was director of the Cavendish Laboratory at the University
of Cambridge, and one of the most respected scientists in Great
Britain, the scientists present found the news hard to believe.
They thought the atom was the smallest and indivisible part of
matter that could exist. Nevertheless, the electron was the first
elementary particle to be discovered.
April 29:
Rubber patent
In 1820, Thomas Hancock's first patent was dated. It was for the
application of rubber in clothing where some elasticity was useful,
such as braces (suspenders) or slip-on boots. Thus began his wish
to find uses for rubber, which until then had limited worth due
to its poor properties, being hard and liable to crack in winter
cold and sticky in summer heat. Later, he invented a "masticator"
which fed waste rubber through a spiked roller rotating in a hollow
cyclinder and produced a homogeneous mass of solid rubber resulting
from the pressure appled and heat generated during the process.
When rolled into sheets or compacted into blocks, the product
was suitable to make various articles. Thus, he became the founder
of the British rubber industry.
April 28:
J. Willard Gibbs
(Born February 11, 1839: Died April 28, 1903)
Josiah Willard Gibbs was a theoretical physicist and chemist who
was one of the greatest scientists in the U.S. in the 19th century.
His application of thermodynamic theory converted a large part
of physical chemistry from an empirical into a deductive science.
April 27:
Wallace Hume Carothers
(Born April 27, 1896: Died April 29, 1937)
American chemist who developed nylon (1935), the first synthetic
polymer fibre to be spun from a melt. He produced this polyamide,
by condensation of adipic acid and hexamethylenediamine. He worked
for the duPont chemical company as head of organic chemistry research
from 1928. Through his study of long-chain molecules, now called
polymers, he also developed the first successful synthetic rubber,
neoprene (1931). He suffered from depression, and died by suicide
at the age of 41 before nylon had been commercially exploited.
DuPont produced nylon commercially from 1938 and laid the foundation
of the synthetic-fibre industry. Nylon proved outstanding in its
properties as a synthetic analog of silk.
April 26:
Sir Owen Willians Richardson
(Born April 26, 1879: Died February 15, 1959).
English physicist who was awarded the Nobel Prize for Physics
in 1928 for "his work on the thermionic phenomenon [electron
emission by hot metals] and especially for the discovery of the
law named after him." This effect is why a heated filament
in a vacuum tube releases a current of electrons to travel an
anode, which was essential for the development of such applications
as radio amplifiers or a TV cathode ray tube. Richardson's law
mathematically relates how the electron emission increases as
the absolute temperature of the metal surface is raised. He also
conducted research on photoelectric effects, the gyromagnetic
effect, the emission of electrons by chemical reactions, soft
X-rays, and the spectrum of hydrogen.
April 25:
Anders Celsius
(Born November 27, 1701: Died April 25, 1744)
Swedish astronomer, physicist and mathematician who is famous
for the temperature scale he developed. Celsius was born in Uppsala
where he succeeded his father as professor of astronomy in 1730.
It was there also that he built Sweden's first observatory in
1741. He and his assistant Olof Hiortner discovered that aurora
borealis influence compass needles. Celsius' fixed scale (often
called centigrade scale) for measuring temperature defines zero
degrees as the temperature at which water freezes, and 100 degrees
as the temperature at which water boils. This scale, an inverted
form of Celsius' original design, was adopted as the standard
and is still used in almost all scientific work.
April 24:
IBM-PC
In 1981, the first IBM personal computer was introduced.
April 23:
Battery
In 1940, a leak-proof flashlight battery
(Ray-o-Vac) was patented in the U.S. by Herman Anthony (No. 2,198,423).
April 22:
Emilio Segrè
(Born February 1, 1905: Died April 22, 1989)
Italian-born American physicist who was cowinner, with Owen Chamberlain
of the United States, of the Nobel Prize for Physics in 1959 for
the discovery of the antiproton, an antiparticle having the same
mass as a proton but opposite in electrical charge.
April 21:
Samuel Slater
(Born June 17, 1768: Died April 21, 1835)
English-American mechanical engineer who founded the American
cotton-textile industry. Before immigrating to the U.S. in 1789,
Slater apprenticed with Jedediah Strutt (partner of Richard Arkwright)
in England. Once in the U.S., he found backing to build Arkwright’s
spinning and carding machinery, with which he established the
first successful cotton mill in the U.S. as well as many others
in the New England region.
April 20:
Karl Alex Müller
(Born April 20, 1927)
Swiss physicist who, along with J. Georg Bednorz, was awarded
the 1987 Nobel Prize for Physics for their joint discovery of
superconductivity in certain substances at higher temperatures
than had previously been thought attainable. They startled the
world by reporting superconductivity in a layered, ceramic material
at a then-record-high temperature of 33 degrees above absolute
zero. Their discovery set new research worldwide into related
materials that yielded dozens of new superconductors, eventually
reaching a transition temperature of 135 kelvin.
April 19:
Zygmunt Florenty von Wroblewski
(Born October 28, 1845: Died April 19, 1888)
Polish physicist who liquefied the "permanent gases"
such as nitrogen and carbon monoxide in larger quantities than
previously accomplished by Cailletet, whose method he improved.
In 1883, he achieved the static liquefaction of oxygen and air.
He was the first to liquify hydrogen. Although he achieved it
only in a transient fine mist, he published (1885) remarkably
accurate data: critical temperature 33 K, critical pressure, 13.3
atm and boiling point, 23 K (modern values 33.3 K, 12.8 atm, 20.3
K). He may also have had a hint of strange electrical properties
at very low temperatures, but his research was cut short upon
his accidental death. Wroblewski died as a result of burns in
a fire started when he overturned a kerosene lamp in his laboratory.
April 18:
Sir John Ambrose Fleming
(Born November 29, 1849: Died April 18, 1945)
English engineer who made numerous contributions to electronics,
photometry, electric measurements, and wireless telegraphy. In
1904, he discovered the one directional current effect between
a positively biassed electrode, which he called the anode, and
the heated filament in an evacuated glass tube; the electrons
flowed from filament to anode only. Fleming called the device
a diode because it contained two electrodes, the anode and the
heated filament. He noted that when an alternating current was
applied, only the positive halves of the waves were passed - that
is, the wave was rectified (from a.c. to d.c.). It would also
take a radio frequency wave and produce d.c.corresponding to the
on and off of the Morse code transmitted signals.
April 17:
Jean Perrin
(Born September 30, 1871: Died April 17, 1942)
Jean-Baptiste Perrin was a French physicist who, in his studies
of the Brownian motion of minute particles suspended in liquids,
verified Albert Einstein's explanation of this phenomenon and
thereby confirmed the atomic nature of matter. Using a gamboge
emulsion, Perrin was able to determine by a new method, one of
the most important physical constants, Avogadro's number (the
number of molecules of a substance in so many grams as indicated
by the molecular weight, for example, the number of molecules
in two grams of hydrogen). The value obtained corresponded, within
the limits of error, to that given by the kinetic theory of gases.
For this achievement he was honoured with the Nobel Prize for
Physics in 1926.
April 16:
Thomas Blanchard
(Born June 24, 1788: Died April 16, 1864):
American inventor who made major contributions to the development
of machine tools.
April 15:
Johannes Stark
(Born April 15, 1874: Died June 21, 1957)
German physicist who won the 1919 Nobel Prize for Physics for
his discovery in 1913 that an electric field would cause splitting
of the lines in the spectrum of light emitted by a luminous substance;
the phenomenon is called the Stark effect.
April 14:
ENIAC proposed to Army
In 1943, a proposal for an electronic computer was submitted to
colleagues at the U.S. Army's Ballistics Research Laboratory by
John Grist Brainerd, director of research at the University of
Pennsylvania's Moore School, where the proposal was written by
John Mauchly. In May 1943, the Army contracted the Moore School
to build ENIAC, the first electronic computer. Although ENIAC
was not finished until after the war had ended, it nevertheless
marked a major step forward in computing.
April 13:
Microscope
In 1625, the word "microscope" was coined as a suggested
term in a letter written by Johannes Faber of Bamberg, Germany,
to Federigo Cesi, Duke of Aquasparata and founder of Italy's Accademia
dei Lincei (Academy of the Lynx). This Academy, possibly the world's
first scientific society took its name after the animal for its
exceptional vision.
April 12:
Internet spam
In 1994, the first Internet spamming program was used by an attorney
in Arizona. Laurence Canter created the software program, a simple
Perl script, that flooded Usenet message board readers with a
notice for the "Green Card Lottery" to solicit business
for his law firm of Canter & Siegel (with wife, Martha Siegel.)
The reaction from the online community was vigorously critical,
condemning such a form of advertising. Thousands of recipients
complained, but a new, burgeoning business of unsolicited mass
Internet advertising had been spawned. The term "spam"
was coined from a sketch in the "Monty Python's Flying Circus"
BBC television show in which a waitress offered a menu full of
variations of spam to an unwilling patron.
April 11:
Electricity lecture
In 1751, Ebenezer Kinnersley advertised in the Pennsylvania
Gazette that he was to give a lecture on "The Newly Discovered
Electrical Fire." His lectures were the first of the kind
in America or Europe. The announcement read: "Notice is hereby
given to the Curious, that Wednesday next, Mr. Kinnersley proposes
to begin a course of experiments on the newly discovered Electrical
Fire, containing not only the most curious of those that have
been made and published in Europe, but a considerable number of
new ones lately made in this city, to be accompanied with methodical
Lectures on the nature and properties of that wonderful element."
Thus, Kinnersley was one of the earliest popularizers of science.
April 10:
Paul-Louis-Toussaint Héroult
(Born April 10, 1863: Died May 9, 1914)
French chemist who invented the electric-arc furnace, widely used
in making steel; and, independently of the simultaneous work of
Charles M. Hall of the United States, devised the electrolytic
process for preparing aluminum. This process made low-priced aluminum
available for the first time, securing the widespread use of the
metal and its alloys.
April 9:
J. Presper Eckert, Jr.
(Born April 9, 1919: Died June 3, 1995)
John Presper Eckert, Jr. was an American engineer and coinventor
of the first general-purpose electronic computer, a digital machine
that was the prototype for most computers in use today. In 1946,
Eckert with John W. Mauchly fulfilled a government contract to
build a digital computer to be used by the U.S. Army for military
calculations. They named it ENIAC for Electronic Numerical Integrator
and Computer. By 1949, they had started a manufacturing company
for their BINAC computer. This was followed by a business oriented
computer, UNIVAC (1951), which was put to many uses and spurred
the growth of the computer industry. By 1966 Eckert held 85 patents,
mostly for electronic inventions.
April 8:
Johann Salamo Christoph Schweigger
(Born April 8, 1779: Died September 6, 1857)
German physicist who invented the galvanometer (1820), a device
to measure the strength of an electric current. He developed the
principle from Oersted's experiment (1819) which showed that current
in a wire will deflect a compass needle. Schweigger realized that
suggested a basic measuring instrument, since a stronger current
would produce a larger deflection, and he increased the effect
by winding the wire many times in a coil around the magnetic needle.
He named this instrument a "galvanometer" in honour
of Luigi Galvani, the professor who gave Volta the idea for the
first battery. Seebeck (1770-1831) named the innovative coil,
Schweigger's multiplier. It became the basis of moving coil instruments
and loudspeakers.
April 7:
Telegraph
In 1885, Granville T. Woods, a prolific black American inventor,
patented an "Apparatus for Transmission of Messages by Electricity,"
No. 315,368. In the following years he introduced numerous innovations
for use on railroads, applying electricity for telegraphy, brakes,
overhead conductors, controls and an electric railway.
April 6:
Horst L. Störmer
(Born April 6, 1949)
Horst Ludwig Störmer is a German-born American physicist
who shared (with Daniel C. Tsui and Robert B. Laughlin) the 1998
Nobel Prize in Physics for the discovery "of a new form of
quantum fluid with fractionally charged excitations." By
experiment using extremely powerful magnetic fields and low temperatures,
in 1982, Störmer and Tsui found that electrons acting together
in strong magnetic fields can form new types of "particles",
with charges that are fractions of electron charges. Within a
year. Laughlin made a theoretical analysis explaining their result.
April 5:
Ivar Giaever
(Born April 5, 1929)
Norwegian-born American physicist who, for his experimental discoveries
regarding tunneling phenomena in superconductors, shared the Nobel
Prize for Physics in 1973 with Leo Esaki and Brian Josephson for
work in solid-state physics. Giaever demonstrated (1960) the tunneling
of electrons through a sandwich with an extremely thin oxide layer
surrounded with metal either in superconducting state on both
sides or in superconducting state on one side and in normal state
on the other side. This gave direct evidence for the so called
energy gap in a superconductor (predicted by Bardeen et al., in
1972). Later, Giaever developed the method into a very powerful
and accurate spectroscopy to study the detailed properties of
superconductors.
April 4:
Zénobe-Théophile
Gramme
(Born April 4, 1826: Died January 20, 1901)
French electrical engineer and inventor (1869) of the Gramme dynamo,
a continuous-current electrical generator that gave principal
impetus to the development of electric power. In 1870 he invented
a continuous-current dynamo with a ring armature (a ring of soft
iron around which were placed insulated copper coils). This produced
much higher voltages than other dynamos of the time and was the
first high-voltage direct-current generator practical for mass
production and distribution. Driven by steam-engines, they were
immediately successful and were used for a variety of purposes,
including factory lighting, electroplating, and lighthouses. With
these dynamos, the era of large-scale electrical engineering began.
April 3:
First cell phone call
In 1973, the first portable phone call was placed by inventor
Martin Cooper. The phone was 10
inches in height, 3 inches deep and an inch-and-a-half wide and
weighed 30-oz. Since then, cell phones have shrunk to a mere palm-size
weighing 4-oz, and are used by a billion people around the world.
Cooper's first ''shoebox'' phone replaced a car phone of the time
that weighed more than 30 pounds and cost thousands of dollars.
A car phone owner had to drill a hole in his car to install the
antenna and most of the phone sat in the trunk. A control unit
with a handset was placed inside the car.
April 2:
Aluminium process
In 1889, Charles M. Hall patented an inexpensive electrolytic
process to extract aluminium from its ore (No. 400,655). Although
aluminum is the most abundant metal in the earth's crust, it is
not found naturally in pure form, and thus it must be separated
from its surrounding ore.
April 1:
François-Marie Raoult
(Born May 10, 1830: Died April 1, 1901)
French chemist who formulated a law on solutions (called Raoult's
law) that made it possible to determine the molecular weights
of dissolved substances.
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