Presentation is loading. Please wait.

Presentation is loading. Please wait.

How do we know about the past?

Similar presentations

Presentation on theme: "How do we know about the past?"— Presentation transcript:

1 How do we know about the past?
Methods of Historical Investigation

2 Primary and secondary sources
Primary sources are those that come from the time being investigated. Secondary sources are written or produced after the period they describe. Letters Speeches Eyewitness description Official documents Modern historian Textbook Encyclopaedia Re-enactments

3 Types of Sources Histories Plays and poetry Legends Letters
Written Sources include: Non-written Sources include: Histories Plays and poetry Legends Letters Inscriptions Laws Administrative Records Graffiti Buildings Monuments Tombs Skeletal remains Pottery Tools and weapons Household goods Coins

4 How reliable are our written sources?
Truth or bias? Purpose for writing Personal beliefs or opinions Limited access to evidence

5 What is Archaeology? Archaeology is a way of studying the human past through physical remains (artefacts). Artefacts are any objects made, used or modified by humans. Archaeologists are Time Detectives

6 Investigating the Evidence
Observation Where was the artefact located? What is its possible age? Who made it? What might it have been used for? Who put it there? Classification & Recording Classifying according to time and place Is it authentic? What can be learnt from it? Does it contradict or complement other evidence from the site? Interpretation Interpret the evidence Look for patterns What conclusions, inferences or assumptions can be drawn?

7 How are artefacts dated?
Relative Dating Methods Absolute Dating Methods Stratification Typology Cross-dating Fluorine testing Paleontological dating Pollen analysis Carbon-14 dating Potassium-argon dating Dendochronology Thermoluminescence Intel Education: Student Login

8 Stratification

9 Typology Many artefacts can be dated according to their style. For example, pottery, tools and weapons show distinct styles at different periods of development (compare with how models of cars have changed over the years).

10 Cross-dating If a particular style of helmet, pottery, etc is able to be dated at one particular site, then this can be used to date other sites in which the same style of artefact is found.

11 Fluorine Testing

12 Paleontological Dating
Palaeontologists study the history of animals. Often a site can be dated according to the types of animal fossils found there.

13 Pollen Analysis Cranesmoor bog is formed over lake muds estimated from pollen analysis to have been laid down in early Boreal times, and the overlying peat is up to 15 feet deep in parts. The peat consists mainly of either Sphagnum or Schoenus nigricans remains, and the present surface vegetation shows a similar variation associated with hydrological differences in different parts of the bog. [Information from a botany report available on the "New Forest History" website: ]

14 Carbon-14 Dating

15 Potassium-argon Dating
The landscape in the central Andes Mountains, near the border between Chile and Argentina, is dominated by volcanoes and associated landforms. Layers of older sedimentary rocks are visible to the upper middle, and many volcanic cones show grooves where water has eroded the rock to form gullies. A few volcanoes exhibit much less erosion, and even show tongues of dark, recent lava flows (upper left).

16 Dendrochronology Sample from wood is taken with hollow drill. Samples from woods those have partly different age, can combine together to make tree-ring sequence, that can be presented like thicker tree or longer stick. Drill to take samples for Dendrochronology from trees

17 Thermoluminescence

18 Comparative Chart: Dating Methods
Can tell us: Accuracy What ? Any Problems Stratification The order of occupation Relative only – earlier or later Any finds in situ Typology Approximate date made Relative only - new/late model Man-made items Cross-dating Not earlier than... Relative: one find used to date other Fluorine Testing Time of burial Relative only (see problems) Bones, teeth, antlers, ivory Temperature Soil chemistry Paleontological What animals? Appearance and extinction period Animals Pollen Analysis Evidence of climate Grains will survive for 1000s of years Plants Only history of the vegetation Carbon-14 Time of death + or – 100 years To 50,000 years Organic material (certain amount) Destruction Contamination Potassium-Argon Age of rock layers To millions of years Volcanic Rock Limited sites Dendrochronology Age of timber Dates layer to year Timber Requires time sequence Thermo-luminescence Original firing date > Typology To 35, 000 years Fired pottery & clay

Download ppt "How do we know about the past?"

Similar presentations

Ads by Google