THE BEGINNINGS OF CHEMISTRY


The name of “elements” (stoicheia) was first used by Plato (427 –347 BC), who assumed that things are produced from a formless primary matter, perhaps just space, taking on “forms”. Aristotle (384 –322 BC) developed the view that all substances were made of a primary matter, called “hulé”. Aristotle defined an element or “simple body” as “one of those bodies into which other bodies can be decomposed and which itself is not capable of being divided into others”.

Aristotle took as the fundamental properties of matter. By combining these in pairs, he obtained what are called “THE FOUR ELEMENTS”. This theory persisted until towars the end of 18th century.
The Four Element
Aristotle’s idea :
  1. Early idea of transmutation
  2. He distinguished between mechanical mixture and solution and chemical change with complete change of properties.
  3. Mercury as “silver water” (chutos arguros)
  4. He says that the vapour from sea water evaporated in a vessel condenses as a fresh water on the cool lid and (wrongly) that wine would give water in a similar way (DISTILLATION)
  5. He concluded that metals are mostly water.
The first clear expression of the idea of an element occurs in the teachings of the Greek philosophers.
  1. Thales (640 –546 BC) supposed that all things were formed of water;
  2. Anaxinemes (560 –500 BC) of air;
  3. Herakleitos (536 –470 BC) of fire;
  4. Empedokles (490 –430 BC) introduced the ideas of four “roots” of things: fire, air, water, earth; and two forces, attraction and repulsion which joined and separated them.

CHEMICAL KNOWLEDGE OF CLASSICAL PERIOD

Dioskurides (60M) and Pliny the Elder (23–79M, the author of the famous “HistoryofNature”) were described several chemical substances, such as the oxide of copper, iron, and zinc; alum; the sulphates of copper and iron; vegetable and animal products, including dyes, and with some simple chemical operations, such as the working of metal and alloys, amalgams, and testing gold and silver for purity.

Theophrastos (315 BC) describing some chemical operations, e.g. manufacture of white lead (Greek, psimuthion).

“lead is placed in an earthen vessel over sharp vinegar and after it has aquired some thickness of a kind of rust, which it commonly does in about ten days, they open the vessels nad scrape it off. They then place the lead over the vinegar again, repeating over and over again the same process of scraping it till it is wholly gone. What has been scraped off they then beat to powder and boil (with water) for a long time and what at last settles to the bottom of the vessel is white lead” (Treatise on Stones)

Pliny describes the preparation of mercury :

“They put minium (cinnabar from Spain) in an earthen vessel well luted over with clay, upon which there is set a pan of iron, and the same covered over the head with another pot, well cemented. Under the earthen pot a good fire is made and kept continually blown. And thus by circulation there will appear a dew or sweat in the upper most vessel, proceeding from the vapours set free. When this is wiped off it will be as liquid as water but in color will resemble silver”

THE CHEMICAL PAPIRY (Leyden papyrus)

A collection of Egyptian recipes discovered in 1928 in a tomb at Thebes in Egypt. The papyrus is writen in Greek at a date probably round 300 M.

“One powders up gold and lead into a powder as fine as flour, 2 parts of lead for 1 of gold and having mixed them, works them up with gum. One covers a copper ring with the mixture; then heats. One repeats several times until the object has taken the color. It is difficult to detect the fraud, since the touchstone gives the mark of true gold. The heat consumes the lead but not the gold”

Mix together and put into a pot 2 grams of malachite, 2 grams of azurite, 130 cc of the urine of a young boy and 180 cc of solution of ox-gall. Put into the pot all the twenty-four pieces of stone, each weighing of 27 grams. Put the lid on the pot and lute it around with clay. Heat for six hours over a gentle fire of olive wood. When you see the lid has become green, do not heat any more but allow to cool and take out the stones, when you will find that they have become emeralds.



ALEXANDRIA

It was a modern city in Egypt which was founded by Alexander the Great at the mouth of the Nile river in 331 BC. This city had a mixed popultion of native Egyptian, Greeks, Syrian, and Jews, but was essentially Greek in culture. It contained a temple of the god Serapis, two Libraries and Museum (or university?).

The name of “chemistry” first occur in Alexandria in 296 M, the Emperor Diocleitian. There was a book, which had the title “chëmeia”. The contents of this book were making (imitating) gold and silver.

The word appears in the Greek autors who report this as “χημεία” in a Greek manuscript now at St. Mark’s in Venice, from a work by Zosomos of Panopolis (300 M).

Illustrations of Chemical Apparatus (Zosimos)A, B, C, F : distillation (Ambix /Alembic)

The lower part is called “lopas” and the upper “phiale”D : sublimation (Kerotakis)E : heating apparatus



“χημεία“ or “chëmeia” probably meant “the Egyptian art” and never had the meaning of a “black art” applied to magic. The work of Zosimos contains interesting descriptions and illustrations of chemical apparatus and experiments, but also some mystical matter.

PLANET                                           

Ηλιος          Sun                                         
Σεληνη        Moon                                      
Κρουος       Saturn                                    
Ζευς            Jupiter                                    
Αρης           Mars                                       
Αφροδντη   Venus                                     
Ερμης         Mercury      

The important feature of Alexandrian treatises was “transmutations”. The process was to be effected by “changing the color”, e.g. Copper turned white by arsenic.

The transmutting agent was latter called by the Arabs “aliksir” (elixir).

Another things to note is that Zosimos distinguishes between what he calls “bodies”, by which he usually means metals, and “spirits”, by which he understands the vapours of arsenic, sulphur and mercury, which exert a powerful action on metals.


Source :
History of Chemistry materials
International Chemistry Education 2011
Yogyakarta State University

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