The Mammoth Activity Book of Prehistory
Who were the first People?
The Stone Age
Stone Age, Bone Age!
Stone Age Boy
Stone Age Sentinel
The Man in the Ice
The Iron Age
Ötzi the Ice Man paper doll
Why do the artefacts have numbers on them?
The artefacts in the loan box are part of the Godalming Museum collection. There are over 25,000 objects in the museum collection. Each one has its own unique identification number so we can keep track of where and what it is.
How do we know how old the artefacts are?
Archaeologists date artefacts in lots of different ways. Here are some of them (see also page 5 of Hidden Depths):-
Objects found deeper down are older than objects found higher up
Human activity leaves evidence in the ground. For instance, a big fire might leave a black burnt layer. Pulling down a building might leave a layer of broken bricks and stones. For as long as humans live on a site, the evidence of their activities is building up in layers. When archaeologists excavate a site they study the layers to work out what has happened in the past. They know that the objects in the lowest layer are the oldest. Archaeologists have to be careful when they study the stratigraphy of a site – what if someone has dug a ditch or a hole and dropped an object down it?
Objects which look the same are a similar date
Objects develop logically so that more sophisticated objects are more recent
There have always been changes in fashion. The decoration on a pot or the shape of a sword can help an archaeologist date the artefact – just as we can tell that a long dress with a bustle is Victorian.
Humans learn all the time. We learn to use new materials: the first tools were stone, then we started to work with metal, first copper, then bronze, then iron. We improve by practicing and we invent new techniques and tools to help us. Early prehistoric pottery was hand made and fired in a bonfire. The sides of the pots are thick and the clay is quite coarse and varies in colour, depending on how much oxygen got in while it was being fired. Roman potters used potters’ wheels and fired their pots at high temperatures in a kiln. Roman pots are elegant and strong and a consistent colour. However Saxon potters went back to making hand made pottery; a reminder of the limits of this method of dating.
Counting tree rings
Trees put on a growth ring every year. If the weather is good they grow well and put on a thick ring. If it is poor (for instance if it is too dry) the tree only puts on a thin ring. Archaeologists can study the sequence of thick and thin tree rings and compare them to a reference sequence to establish the date of a piece of wood. The wood has to have at least 50 tree rings for this to be possible. Godalming Museum is in a timber framed building which has been dated by dendrochronology. The dendrochronologists took several samples. They cut off the end of one wooden beam and drilled a hole into another. They were able to date the building to 1446. The samples they took are on display at the museum.
A scientific method of dating which only works on organic material
All living things contain a chemical called Carbon 14. When the plant or animal dies the Carbon 14 it contains starts to decay. By measuring the amount of Carbon 14 left in any organic material, archaeologists can work out when it died.
Willard Libby who invented this method of dating was awarded the Nobel prize for this work in 1960.
The earth’s magnetic field is constantly changing. When a piece of clay like a pot or a brick, is fired it creates a record or snapshot of the earth’s magnetic field as it was at the moment the clay reached the critical temperature (the Curie point). Archaeologists can compare this with records of how the earth’s magnetic field has changed, to work out the date when the clay was fired.
Dating using vole teeth
Archaeologists have established how voles have evolved. Changes to voles’ teeth are particularly helpful. If an archaeologist finds vole remains on a site, they can compare them to the established sequence of vole development to date their site.
Flint is an amazingly useful stone which was Stone Age people’s favourite material for making tools. It is a strong stone which breaks predictably and can produce a very sharp edge. Two flints struck together will produce a spark and, in more modern times, a flint and a steel was the standard fire lighting kit. Ötzi’s the Ice Man’s fire lighting kit consisted of flint, iron pyrites and dried fungus.
Flint is found in nodules in sedimentary rocks like chalk. It formed from silica, although Geologists don’t know exactly how. In the local area, flint is found in the North Downs.
Click here for notes on the prehistory of the local area Link to Notes Page (3.2)
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