Archeology, Archaeology

A metal grating at the gateway of a castle: In the story, the portcullis was dropped into place at the front of the doorway of the medieval castle to ward off the enemy and to defend those inside the fort.

A fragment of a ceramic vessel: The potsherd, or piece of broken pottery, that the archeologist discovered at the site was handled very carefully.

Regarding the time in history of the Western Hemisphere before 1492 A.D.: The pre-Columbian era of history existed in the Americas prior to the first contact by that was made by Christopher Columbus (1492 A.D.)

It is often used synonymously with "prehispanic".

The period of history in the Americas prior to the invasion by Spain in the 16th century: The prehispanic time is the era previous to the Spanish accusitions or conquests in the western hemisphere

That period of the human past that predates the emergence of writing systems: Jane was interested in the prehistory of people, of of the time before written records were discovered.

An absolute dating system of assessing the age or determining a date of an artifact: Radiocarbon dating was invented by the American chemist Willard f. Libby (1908-1980) while conducting atom bomb research.

Today the method can provide a reliable date using a single grain of wheat.

It takes advantage of the fact that all organic materials contain mesurable amounts of radioactive carbon (Carbon 14).

At death, the radiocarbon begins to disintegrate at a known rate. By measuring the amount of radioactive carbon left, scientists can determine how long ago the organism died.

The latest versions of the technique can date objects up to 70,000 years old.

An ancient Greek drinking or pouring horn or vessel: At the museum, Sam viewed a rayton that was shaped in the form of an animal's head.

Any system of dating that is not based on a calendrical system: By using relative dating, artifacts or sites are described as being earlier or later than other artifacts or sites.

A tool consisting of metal probes which have an electric current passed between them while they are inserted into the soil: The resistivity meter is an instrument used to measure the variable resistivity of soils, that is the amount of resistance to the flow of electricity within it.

A soil’s resistivity is a product of the amount of moisture in the soil and its distribution. It varies considerably, and these variations can reflect the presence of buried archaeological features.

Ditches and pits, for example, hold a greater amount of moisture than the surrounding natural soil, and so they are less resistant, whereas solid features like walls are more resistant.

A branch of the Afroasiatic language family: The Semitic languages include Akkadian, Arabic, Aramaic, Ethiopian, Hebrew, and Phoenician among other ancient and modern languages, and are spoken by more than 330 million people.

In archaeology, a place where people used to live together in ancient times: The term settlement is used most often in Egypt and Mesopotamia.

Soapstone; a large piece of talc: In school, Mark learned that steatites, relatively soft stones, were valued for carving because they were comparatively soft

An ancient upright stone slab bearing markings: A stela was used as a commemorative, or for a similar function, on which was carved an inscription or other design.

A large, relatively flat and treeless, grassland plain: Typical steppes, where grass is the dominant form of plant life, can be found in Eastern Europe and Asia.

A generic term for that period of the human past in which stone, bone, and wood were the primary raw materials from which tools were made: The Stone Age was a very early time of human history when people made tools and weapons from stone, but not of metal.

It covers the Paleolithic, Mesolithic, and Neolithic periods.