Humans have explored the world around them ever since they first stepped onto their feet and walked. First, they mastered the unique tool given by nature to mankind - their hands. Gradually, they learned how to benefit from the material world by establishing new technologies, thus giving us reason to name the periods of development of mankind after the new basic materials they used: Stone Age, Chalcolithic (Copper-Stone Age), Bronze Age, Iron Age.

The lands of present day Bulgaria were an important part of the Old World, but are neglected by scholars today as an important centre for the study of ancient technologies. However, the oldest evidence of human activities in Europe is found namely in our lands (the finds from the Kozarnika Cave); the oldest remains of Homo Sapiens in Europe are also found in present day Bulgaria (in the Bacho Kiro Cave near Gabrovo); the oldest man-made gold - that is, not simply hammered native gold, but melted and cast gold - was found on Bulgarian soil (the artefacts from the Varna Chalcolithic necropolis); and examples of the oldest niello (metal alloy) decoration were also discovered here (the Vulchitrun Gold Treasure).

This series of articles would like to acquaint readers with some aspects of the development of mankind by telling short stories about "man the maker" and by introducing interesting examples from Bulgaria and from the collections of the National Museum of History in Sofia.

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One of the first great achievements of humans was the mastering of fire. People quickly realised and exploited its potential. Thus, from the very beginning, the development of humankind depended on additional sources of energy.

At the time when people discovered pottery, they had already had thousands of years of experience in surviving among beasts and the furies of nature, and they knew that fire changed the properties of many things. Namely, this gave them the opportunity to paint beautiful pictures in caves, supplying them with a rich palette of mineral pigments. They had learned to treat stones and to make various tools and weapons from wood and stone. They also knew how to give brilliant polish to special stone items. However, pottery was the first real chemical technology, and a great and crucial discovery for mankind, as people treated raw materials (clay) of certain qualities to achieve a new material (pottery) of completely different qualities.

It is hard to determine the exact time when people started to make objects of clay, to dry and bake them, but surely some accident had given them the idea: a camp fire on dry, cracked clay-giving soil would have produced an irregular convex pottery "plate"; the habit of some peoples of building cooking fires in clay-coated shallow holes in the floors of their houses would have resulted in a shallow pottery vessel set into the ground; the woven baskets that other peoples coated on the inside with clay would have also produced a pottery container if one of them had accidentally fallen into a fire and burned. Any of these, or some other accident, might have given the idea to ancient humans, as survival depended on keenness of observation and inventiveness.

Pottery may no longer be very important in our lives, but it was extremely important in ancient times. However, people did not realise at once the greatness of their discovery, as they continued to lead a nomadic way of life and it was not convenient for them to carry large, heavy containers. The Stone Age tribes needed strong, light vessels for their journeys, and pottery was heavy and easily broken. When people established settlements and started to grow their own food, they immediately realised the advantages of the pottery containers for keeping their food from the animals during winter, for a longer storage of liquids, etc. On the other hand, the discovery of pottery had a big impact on cooking and broadened the sources of food, and most important - made possible the development of metallurgy and glass technologies. Ancient people also quickly developed various decorative techniques, showing us their sense of beauty.

The lands of present day Bulgaria provide archaeological evidence of the brilliant prehistoric civilization of the "first Europeans". Thousands and thousands of prehistoric objects are stored and on display in many museums in Bulgaria, including: the National Museum of History (Sofia), The Institute of Archaeology with Museum (Sofia), Plovdiv Archaeological Museum, Varna Archaeological Museum, the Neolithic Dwellings Museum (part of the Museum of History in Stara Zagora).

The vessels from the 5th - 4th millennium BCE are amazing. They display a large variety of styles, shapes and decorative patterns and demonstrate an understanding of the manufacturing technology and creativeness in decoration. For example, the makers knew that certain types of clay (those free of iron oxides) do not change their colour after being subjected to fire treatment, while others do change. Moreover, they knew that the after-baking colour of the latter clay depends on the atmosphere in the pottery kiln - black in a reduced atmosphere (oxygen-free and rich in reducing agents), and red in an oxidizing atmosphere (rich in oxygen). They produced marvellous pottery: white ornaments, or objects with burnished surfaces decorated with geometric patterns in black and red, outlined with white inlaid incised lines. Some examples from Durankulak, in northeastern Bulgaria, of this first application of what was to become the famous black- and red-figure ceramics (1st  millennium BCE), along with other interesting, beautiful objects from the prehistoric period of the Bulgarian lands, are on display in Hall 1 of the National Museum of History.

Svetla Tsaneva heads the central conservation and restoration laboratory at the National Museum of History. She was a specialist in the chair of conservation and restoration at the National Academy of Fine and Applied Arts and has lectured on general conservation and the history of glass at New Bulgarian University. As a restorer, she has worked on many major exhibitions in Bulgaria and abroad. She has co-authored and translated numerous publications. She has a BA in atomic physics and an MA in optics and spectroscopy, has conservation practice in metals, glass and ceramics and has conducted scientific research in materials science, archaeometry and ancient technologies.