Luigi Galvani (1737-1798) 
In the mid-1780s, anatomist Luigi Galvani (Bologna, Italy) was studying the
effects of atmospheric electrical discharge. One day, in his garden, he fastened
brass hooks between the spinal cord of a dissected frog and an iron railing.
To his amazement the frog's legs began twitching wildly, not only when lightning
flashed, but also when the sky was calm. Galvani interpreted his results
in terms of animal electricity (incorrect). Galvani proclaimed that the muscle
retained a nerveo-electrical fluid similar to that of an electric eel. While
his papers on the subject ignited research among scientists of Europe, the
most significant consequence of Galvani's discovery was the concept of Galvanism
which refers to the production of electrical current from the contact of
two metals in a moist environment. Shortly before he died, Galvani was dismissed
from his professorship at the University of Bologna, because he refused to
swear allegiance to Napoleon's Republic.
Alessandro Giuseppe Volta (1745-1827) 
Volta was born in Como, Italy (near Milan). In 1774, he began his first academic
position as principal of the state Gymnasium in Como. In 1777, he was appointed
Professor of Physics at the University of Pavia. Here he began to repeat Galvani's
famous experiments with decapitated frogs. He observed that Galvani had connected
brass hooks between the frog's spinal cord and an iron railing. According
to Volta's interpretation, the muscle twitches were induced by current flowing
between two dissimilar metals connected by the moist flesh of the frog's
leg. This led him to develop the first device which demonstrated chemical
production of electric current. In 1799, Volta arranged a vertical pile of
metal discs (zinc with copper or silver) and separated them from each other
with paperboard discs that had been soaked in saline solution. This stack
became known as the voltaic pile and was the first electric battery.
In his pursuit of the current generated by his primitive batteries, Volta
developed several new devices. He invented the electrophore, a forerunner
of the capacitor; the condensatore, a device that detected weak electrical
current; and the straw electrometer, a meteorology tool which measured atmospheric
electricity. The term volt, a unit of electrical measurement, is named in
his honor. In 1801, Volta was summoned to Paris to demonstrate his discovery
before the Academy of Sciences. Napoleon declared his presentation a triumph,
awarded him a gold medal and initiated the annual Volta Prize in his honor.
Humphry Davy (1778-1829)
At 19, Davy began studying chemistry after reading papers by Antoine Lavoisier.
Within five years he was appointed Professor of Chemistry at The Royal Institution
in London. In his first scientific work, Davy investigated the possible therapeutic
value of inhaling various gases, using himself as a guinea pig. Since nitric
oxide (laughing gas) and carbon monoxide were among the gases studied, it
is surprising he survived. Davy utilizes the recently discovered voltaic
pile to lay the qualitative foundations of electrochemistry. Davy isolated
elemental potassium which was soon followed by sodium, barium, calcium, strontium,
and magnesium. Davy later isolated boron and silicon.
Late in 1813, Davy set out on an 18 month tour of Europe accompanied by young
Michael Faraday. Though neither then realized it, Davy's star was beginning
to set while Faraday's was soon to rise. Faraday was to succeed Davy at The
Royal Institution. Some have unkindly suggested that Davy's greatest discovery
was Michael Faraday. Strictly as a chemist, Davy was the greater of the two.
As a scientist, Faraday was incomparable.
Michael Faraday (1791-1867)
Although Faraday came from very humble beginnings, left school at the age
of 12, and was essentially self-taught, he is acknowledged as one of the
greatest of all scientists.Davy was Faraday's mentor in his early years of
physics and electrochemistry research. For a time, in fact, Faraday extended
and developed the research begun by Davy at the Royal Institution in London,
where Faraday began his career in 1813 as Davy's Laboratory Assistant. Most
of Faraday's early experiments and published papers bore the stamp
of Davy's involvement.
Faraday achieved scientific prominence of his own for the First Law of Electrochemistry,
developed in 1834: The chemical power of a current of electricity is in direct
proportion to the absolute quantity of electricity which passes. The Second
Law of Electrochemistry, also defined by Faraday, states: Electrochemical
equivalents coincide, and are the same, with ordinary chemical equivalents.
The work that led to these two laws also resulted in many of the modern electrochemical
terms such as electrode, electrolyte, and ion.
But Faraday didn't consider himself an electrochemist; he preferred the title
of natural philosopher and devoted his life to proving the interconnection
of natural forces. His electrochemical research was one outcome of this effort,
exploring the connection between the chemical and electrical forces of the
voltaic battery.
John Frederic Daniell (1790-1845)
Daniell was born in London and was appointed professor of chemistry at King's
College, London. Daniell's research into development of constant current
cells took place at the same time (late 1830s) that commercial telegraph
systems began to appear. Early telegraph messages were brief and traveled
short distances. Daniell's copper battery (1836) became the standard for
British and American telegraph systems. In 1839, Daniell experimented on
the fusion of metals with a 70-cell battery. He produced an electric arc
so rich in ultraviolet rays that it resulted in an instant, artificial sunburn.
These experiments caused serious injury to Daniell's eyes as well as the
eyes of spectators. Ultimately, Daniell showed that the ion of the metal,
rather than its oxide, carries an electric charge when a metal-salt solution
is electrolyzed.
