The history
of chemistry represents a time span from ancient history to the present. By 1000 BC,
civilizations used technologies that would eventually form the basis of the
various branches of chemistry. Examples include extracting metals from ores,
making pottery and glazes, fermenting beer and wine, extracting chemicals from
plants for medicine and perfume, rendering fat into soap,
making glass, and making alloys like bronze.
The proto-science
of chemistry, alchemy, was unsuccessful in explaining the
nature of matter and its transformations. However, by performing experiments
and recording the results, alchemists set the stage for modern chemistry. The
distinction began to emerge when a clear differentiation was made between
chemistry and alchemy by Robert Boyle in his work The
Sceptical Chymist (1661).
While both alchemy and chemistry are concerned with matter and its
transformations, chemists are seen as applying scientific method to their work.
Chemistry is
considered to have become an established science with the work of Antoine Lavoisier, who developed a law of conservation
of mass that
demanded careful measurement and quantitative observations of chemical
phenomena. The history of chemistry is intertwined with the history
of thermodynamics,
especially through the work of Willard Gibbs.
The earliest
recorded metal employed by humans seems to be gold which
can be found free or "native". Small amounts of natural gold have
been found in Spanish caves used during the late Paleolithic period, c. 40,000
BC.
Silver, copper, tin and meteoric iron can also be found native, allowing
a limited amount of metalworking in ancient cultures. Egyptian
weapons made from meteoric iron in about 3000 BC were highly
prized as "Daggers from Heaven".
Arguably the
first chemical reaction used in a controlled manner was fire. However, for millennia fire was seen simply as a mystical
force that could transform one substance into another (burning wood, or boiling water) while producing heat and light. Fire affected
many aspects of early societies. These ranged from the simplest facets of
everyday life, such as cooking and habitat lighting, to more advanced
technologies, such as pottery, bricks, and melting of metals to make tools.
It was fire
that led to the discovery of glass and the purification of
metals which in turn gave way to the rise of metallurgy. During the early stages of
metallurgy, methods of purification of metals were sought, and gold,
known in ancient Egypt as early as 2900 BC, became a
precious metal.
Certain
metals can be recovered from their ores by simply heating the rocks in a fire:
notably tin, lead and (at a higher temperature)
copper, a process known as smelting. The first evidence of this extractive
metallurgy dates from the 5th and 6th millennium BC, and was found in the
archaeological sites of Majdanpek, Yarmovacand Plocnik,
all three in Serbia. To date, the earliest copper smelting
is found at the Belovode site,[5] these
examples include a copper axe from 5500 BC belonging to the Vinča
culture. Other signs of early metals are found from the third
millennium BC in places like Palmela (Portugal), Los Millares (Spain), and Stonehenge (United Kingdom). However, as
often happens with the study of prehistoric times, the ultimate beginnings
cannot be clearly defined and new discoveries are ongoing.
These first
metals were single ones or as found. By combining copper and tin, a superior
metal could be made, an alloy called bronze, a major technological shift which began the Bronze Age about 3500 BC. The Bronze Age was
period in human cultural development when the most advanced metalworking (at
least in systematic and widespread use) included techniques for smelting copper and tin from
naturally occurring outcroppings of copper ores, and then smelting those ores to cast bronze. These
naturally occurring ores typically included arsenic as a common impurity.
Copper/tin ores are rare, as reflected in the fact that there were no tin
bronzes in western Asia before 3000 BC.
After the
Bronze Age, the history of metallurgy was marked by armies seeking better
weaponry. Countries in Eurasia prospered when they made the superior alloys, which,
in turn, made better armor and better weapons This often determined the
outcomes of battles. Significant progress in metallurgy and alchemy was
made in ancient
India.
The
extraction of iron from its ore into a workable metal
is much more difficult than copper or tin. It appears to have been invented by
the Hittites in about 1200 BC, beginning
the Iron Age. The secret of extracting and working
iron was a key factor in the success of the Philistines.
In
other words, the Iron Age refers to the advent of ferrous
metallurgy. Historical
developments in ferrous metallurgy can be found in a wide variety of past
cultures and civilizations. This includes the ancient and medieval kingdoms and
empires of the Middle East and Near East, ancient Iran, ancient Egypt, ancient Nubia,
and Anatolia(Turkey), Ancient Nok, Carthage, the Greeks and Romans of ancient Europe, medieval Europe, ancient and
medieval China, ancient and medieval India, ancient and medieval Japan, amongst
others. Many applications, practices, and devices associated or
involved in metallurgy were established in ancient China, such as the
innovation of the blast furnace, cast iron, hydraulic-powered trip hammers, and double acting piston bellows.
Democritus, Greek philosopher of
atomistic school.
Philosophical
attempts to rationalize why different substances have different properties
(color, density, smell), exist in different states (gaseous, liquid, and
solid), and react in a different manner when exposed to environments, for
example to water or fire or temperature changes, led ancient philosophers to
postulate the first theories on nature and chemistry. The history of such
philosophical theories that relate to chemistry can probably be traced back to
every single ancient civilization. The common aspect in all these theories was
the attempt to identify a small number of primary classical element that make up all the various
substances in nature. Substances like air, water, and soil/earth, energy forms,
such as fire and light, and more abstract concepts such as ideas, aether, and
heaven, were common in ancient civilizations even in absence of any
cross-fertilization; for example in Greek, Indian, Mayan, and ancient Chinese
philosophies all considered air, water, earth and fire as primary elements.
Around 420
BC, Empedocles stated that all matter is made up
of four
elemental substances—earth,
fire, air and water. The early theory of atomism can be traced back to ancient Greece and ancient India. Greek atomism dates back to the
Greek philosopher Democritus, who declared that matter is composed
of indivisible and indestructible atoms around 380 BC. Leucippus also declared that atoms were the
most indivisible part of matter. This coincided with a similar declaration
by Indian philosopher Kanada in his Vaisheshika sutras around
the same time period. In much the same fashion he discussed the existence
of gases. What Kanada declared by sutra, Democritus declared by
philosophical musing. Both suffered from a lack of empirical data. Without scientific proof,
the existence of atoms was easy to deny. Aristotle opposed the existence of atoms in
330 BC. Earlier, in 380 BC, a Greek text attributed to Polybus argues that the
human body is composed of four humours. Around 300 BC, Epicurus postulated a universe of
indestructible atoms in which man himself is responsible for achieving a
balanced life.
With the
goal of explaining Epicurean philosophy to a Roman audience, the Roman poet and philosopher Lucretius wrote De Rerum Natura (The Nature of Things) in 50 BC.
In the work, Lucretius presents the principles of atomism; the nature of the mind and soul;
explanations of sensation and thought; the development of
the world and its phenomena; and explains a variety of celestial and terrestrial phenomena.
Much of the
early development of purification methods is described by Pliny the Elder in his Naturalis
Historia. He made
attempts to explain those methods, as well as making acute observations of the
state of many minerals.
Comments
Ancient
humans had developed metallurgy through trial and error and were happy with
their gold, copper, bronze and iron. Ancient philosophers didn’t develop their
thoughts using experimentation. Alchemy and astrology riddled with mysticism
was practiced from 50 BC to the 1500s.
Norb
Leahy, Dunwoody GA Tea Party Leader
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