What's Behind the Development of Tools? 

Chantilly, France

What is the secret behind man's capacity and desire to develop more complicated, powerful, precise, sometimes abstract, and specialized tools?

Is it survival that drives him?
Is it curiosity that lures him?
Is it a desire to be the master of his environment that incites him?
Is it a need for stimulation that urges him?

The answer to this question could help to anticipate future technological trends.

I was just in Langres yesterday visiting the Musee d'Art et d'Histoire. The exhibits on Paleo and Neololithic human development and the development of metal working brought me back to this question that has been brewing in the back of my mind when I get a spare minute to think about it.

I'm reading McClellan and Dorns "Science and Technology in World History" that I ordered from Amazon. The authors describe the Paleolithic hunter/gathering liftstyle as a sort of "Garden of Eden", a mode of existence which was not given up willingly. Several hypothesis are put forward to explain why humans moved from the hunter/gatherer mode of existence to the Neolithic settled argricultural existence. One is depletion of resources. The human population had grown to the point where the availablilty of game, wild nuts, fruits, and mushrooms could no longer sustain it.

Does the above theory validate the Biblical account of the early history of Man? Was it the experience of the depletion of natural resources which formed the basis for the story of Cain and Abel? The two seem to represent the new technologies of herding and farming which defind the Neolithic human experience.

And what about the concept of the Noble Savage which was so much a part of Rousseau's philosophy and also the development of the ideas behind the American and French revolutions? Is there a connection?

Fire

The discovery of fire was a key element in the history of the development of tools. Fire provides heat for warmth and hardening wooden tools and for cooking which made digesting food easier. It provides light and protection from wild animals. Without fire, materials which can be used for tools are limited to stone, wood, and animal bones, horns and shells. This also includes plant fibers for basketmaking (because baskets decay easily, it is difficult to establish when this technology first appeared in human history.). Fire opens up a whole new realm of available materials in the use of fired clay, glass, lime (concrete), and metal smelting and forging. Fire also allowed man to more easily work the earlier materials of stone and wood by providing secondary tools for this purpose. The early story of tool development is the story of man being able to achieve higher temperatures from fire and the addition of new chemical processes.

Pottery

The temperature of a fire depends on the material being burned and the environment in which it is burning. Campfire temperatures are said to be in the range of 600-650 C. In discussing the firing of pottery according to Derry and Trevor "Primitive man probably had to be content with firing temperatures in the range of 450C to 700C ... At higher temperatures (750 - 800C) such as can be obtained in large open fires or simple kilns chemical changes take place in the clay, making it stronger and less porous." According to McClellan and Dorn "Neolithic kilns produced temperatures upwards of 900C".

Metallurgy

The discovery of the process for making charcoal permitted an increase in the temperature for fires. Higher temperatures can be achieved through the artificial creation of a draft in a kiln or furnace (as increasing the delivery of air (through a device like a bellows) raises the rate of combustion and therefore the heat output). To make charcoal, wood is burned slowly (smoulders) in an oxygen reduced atmosphere which results in a high carbon content fuel. Charcoal burns at a temperature of 1,100C.

The principal tool making metals were copper, lead, tin, and iron. Most often these were found as ores, combinations of the metal elements with other elements such as oxygen or sulphur. Copper was often found as Malachite (copper carbonate), Chalcocite (copper sulfide), or Cuprite (copper oxide). A temperature of 700-800 C is necessary for reduction of Malachite (copper ore) to produce copper nodules. The melting point of pure copper is 1,083C. Lead was found in the ore Galena (lead sulphide). The production of metallic lead from its ore is relatively easy and could have been produced by reduction of Galena in a camp fire. Lead is highly malleable, ductile and noncorrosive making it an excellent piping material. The most common form of tin ore is Cassiterite (tin oxide). Temperatures in excess of 1200C are required to smelt tin. Iron is found mainly in Hemitite (iron oxide). It must be smelted at temperatures above 1100C. The melting temperature of pure iron is 1,535C.

Smelting involves more than just "melting the metal out of its ore". In most ores, the metal is tightly combined with other elements, such as oxygen (as an oxide) or sulfur (as a sulfide). With the exception of mercury oxide, which decomposes at about 500 C (932 F), these compounds will resist temperatures much higher than those that can be attained in a wood- or coal-burning furnace. Smelting therefore requires providing suitable reducing substances that will combine with those oxidizing elements, freeing the metal. The carbon or carbon monoxide derived from it removes oxygen from the ore to leave the metal. As most ores are impure, it is often necessary to use flux, such as limestone, to remove the accompanying rock gangue as slag.

Historically, the first smelting processes used carbon (in the form of charcoal) to reduce the oxides of tin (cassiterite, SnO2), copper (cuprite, CuO) and lead (Lead(II) oxide, PbO), and eventually iron (hematite, Fe2O3) according to the overall reactions

Bronze

Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It was one of the most innovative alloys of mankind. Tools, weapons, armor, and various building materials like decorative tiles made of bronze were harder and more durable than their stone and copper predecessors. Copper and tin ores are rarely found together, so serious bronze work has always involved trade. Though bronze is stronger (harder) than wrought iron, the Bronze Age gave way to the Iron Age; this happened because iron was easier to find. Bronze was still used during the Iron Age, but for many purposes the weaker wrought iron was found to be sufficiently strong. Archaeologists suspect that a serious disruption of the tin trade precipitated the transition. The population migrations around 1200 1100 BC reduced the shipping of tin around the Mediterranean (and from Great Britain), limiting supplies and raising prices. As ironworking improved, iron became cheaper, and cultures learned how to make steel, which is stronger than bronze and holds a sharper edge longer.

Agriculture

Agriculture provided the basis for civilization in that it generated a food surplus. In the Neolithic period, wheat and other grains were domesticated (first in the fertile crescent and then moving outward to neighboring parts of the world such as Europe). In order to keep a surplus of this grain in a way that it doesn't spoil you need to store it. This spurred the development of basket making and pottery. It also saw the domestication of the cat to protect the grain surplus from rodents.

The first uses of fire probably came in the form of an evident benefit obtained from accidents or unintended outcomes which man learned how to systematically repeat. For example, man may have observed the affect heat has on clay when a fire was built on a hearth of clay.
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