What is Archaeology?

Archaeology

Archaeology is the scientific study of the material remains of past human life and activities. This includes human artifacts from the very earliest stone tools to the man-made objects that are buried or thrown away in the present day. Everything made by human beings - from simple tools to complex machines, from the earliest houses and temples and tombs to palaces, cathedrals, and pyramids is an archaeologyical artefact. Archaeological investigations are one of our principal sources of knowledge on prehistoric, ancient, and extinct cultures.

Archaeologists describe, classify, and analyse the artifacts they study. An adequate and objective taxonomy (classification system) is the basis of all archaeology, and many good archaeologists spend their lives in this activity of description and classification. The main aim of the archaeologist, however, is to place the material remains found into historical contexts, as well as to supplement what may be known from written sources, and, thus, to increase understanding of the past.

Increasingly, many scientific techniques are used by the archaeologist, and he uses the scientific expertise of many persons who are not archaeologists in his work. The artifacts he studies must often be studied in their environmental contexts. Botanists, zoologists, soil scientists, and geologists may be brought in to identify and describe plants, animals, soils, and rocks. Radio-carbon dating, which has revolutionised much of archaeological chronology, is a by-product of research in atomic physics.

The development of scientific archaeology in 19th-century Europe from the antiquarianism and treasure collecting of the previous three centuries was due to three things: a geological revolution, an antiquarian revolution, and the propagation of the doctrine of evolution.

Geology was revolutionised in the early 19th century with the discovery and demonstration of the principles of uniformitarian stratigraphy by men like William Smith, Georges Cuvier, and Charles Lyell. Uniformitarian stratigraphy determines the age of fossil remains by the stratum, or layer, which they occupy below the earth. Lyell, in his Principles of Geology (1830-33), popularised this new system and paved the way for the acceptance of the great antiquity of man. Charles Darwin regarded Lyell's Principles as one of the two founding works in the formation of his own ideas on evolution.

Early stone tools had been identified in Europe since mid-16th century. That they were, however, older than 4004 BC, the date of man's origin according to biblical chronology, was not recognized until late in the 18th century, when John Frere suggested a great age for artefacts found in Suffolk, England, based on their location in certain strata. The discoveries of Jacques Boucher de Perthes in the Somme Valley in France, and of William Pengelly in the caves of South Devon in England, were used to demonstrate the antiquity of man in 1859, the same year that saw the publication of Darwin's revolutionary Origin of Species. Approximate dates for the Palaeolithic Period (Old Stone Age) of the prehistoric past were thus established, although the expression "Palaeolithic" was not used until John Lubbock coined it in his book Prehistoric Times (1865).

Half a century before this, Scandinavian archaeologists had created a revolution in antiquarian thought by postulating, on archaeological grounds, successive technological stages in man's past. C.J. Thomsen classified the material in the Copenhagen Museum, opened to the public in 1819, on the basis of three successive ages of Stone, Bronze, and Iron. His pupil and successor, J.J.A. Worsaae, showed the correctness of this museum arrangement by observed stratigraphy in the Danish peat bogs and barrows (funerary mounds). Low lake levels in Switzerland in the mid-1850s permitted the excavation of the prehistoric Swiss lake dwellings, and here again the theory of a succession of technological stages was confirmed.

Darwin's Origin of Species implied a long past for man, and the acceptance of the idea of human evolution in the last four decades of the 19th century created a climate of thought in which archaeology flourished and that led to great advances in the unfolding of the full story of man's development. In his Prehistoric Times, Lubbock expanded the three-age system of Thomsen and Worsaae to a four-age system, dividing the Stone Age into Old and New periods (Palaeolithic and Neolithic).

In the last quarter of the 19th century remarkable Palaeolithic discoveries were made in France and Spain; these included the discovery and authentication of actual works of sculpture and cave paintings from the Upper (later) Palaeolithic Period (c. 30,000-c. 10,000 BC). When Marcellino de Sautuola discovered the cave paintings at Alta Mira, Spain (1875-80), most experts refused to believe they were Palaeolithic. However, after similar discoveries at Les Eyzies in France around 1900, they were accepted as such and were recognised as one of the most surprising and exciting archaeological discoveries. A succession of similar finds has continued in the 20th century. The most famous of these was at Lascaux, France, in 1940.

During the last quarter of the 19th century, Gen. A.H. Pitt-Rivers' excavations of prehistoric and Roman sites at Cranborne Chase, Dorset, laid the foundations of modern scientific archaeological field technique, which was later developed and improved in England and Wales by men such as Sir Mortimer Wheeler and Sir Cyril Fox.

The 20th century has seen the extension of archaeology outside the areas of the Near East, the Mediterranean, and Europe, to other parts of the world. In the early '20s, excavations at Mohenjo-Daro and Harappa, in present Pakistan, revealed the existence of the prehistoric Indus civilization. In the late '20s, excavations at An-yang in eastern China established the existence of a prehistoric Chinese culture that could be identified with the Shang dynasty of early Chinese records.

The Stone Age has been described and studied throughout the world; among the most sensational discoveries are those of L.S.B. Leakey, who found stone tools and skeletal remains of early man dating back 2,000,000 years in the Olduvai Gorge in Tanzania. Intensive work of great importance has brought to light early Neolithic sites at Jericho in Palestine; Hassuna, Iraq; Çatalhüyük, Turkey; and elsewhere in the Near East, establishing the origins of agriculture in that region.

The enormous growth of archaeological work has meant the establishment of archaeology as an academic discipline; few important universities anywhere in the world are now without professors and departments of archaeology. There are now a very large number of scholarly journals in the field, as well as a considerable body of popularised books and journals that attempt to bridge the gap between professional and layman.

Fieldwork

Preliminary work: Some archaeologists call everything they do out-of-doors fieldwork, but others distinguish between fieldwork, in a narrower sense, and excavation. Fieldwork, in the narrow sense, consists of the discovery and recording of archaeological sites and their examination by methods other than the use of the spade and the trowel. Sites hitherto unknown are discovered by 'field-walking' over a part of the countryside. Such deliberate reconnaissance is an essential part of archaeological fieldwork.

A study of old records and place-names may lead to the discovery of long-forgotten sites. The mapping of new and old sites is an essential part of archaeological survey. This process has been brought to a very high standard of perfection, both in the marking of archaeological sites on ordinary topographical maps and in the production of special period maps. The distribution map of artefacts, especially when studied against the background of the natural environment, is a key method of archaeological study.

The formerly earthbound archaeologist has been greatly helped by the development of aerial photography. The application of aerial photography to archaeological investigation began in a small way during World War I, as a side effect of military reconnaissance, and was given further impetus by World War II. The photographic intelligence departments of all the combatant nations were extensively staffed by archaeologists, who then carried their expertise and enthusiasm into the post-war years.
The University of Cambridge now has its own department of air photography and, using its own pilot and aircraft, it flies photographic missions over Ireland, Great Britain, Denmark, and The Netherlands. The number of new sites discovered each year by aerial photography is very large. Some of these are surface sites, especially partly destroyed sites that show up well in special conditions of light, as in early morning or late evening. But many are sites that could not be found on the ground and that show up in aerial photographs as variations in soil colour or in the density of crop 'crop marks'.

Archaeological surveying may be advanced from ordinary surface or aerial methods in a wide variety of ways. A very simple method is tapping the ground to sound for substructures and inequalities in the subsoil. Deep probes have made it possible to trace walls and ditches. The Lerici Foundation of Milan and Rome has had great success with this method since its development of the Nistri periscope, first used in 1957 in an Etruscan tomb in the cemetery of Monte Abbatone. The periscope is inserted into the burial chamber and can photograph the walls and contents of the whole tomb.

Other modern techniques that have been applied to archaeological prospecting employ electricity and magnetic fields (geophysical prospecting). Geophysics is a method of electrical prospecting whuich had been developed in large-scale oil prospecting. The technique is based on the degree of electrical conductivity present in the soil. It began to be used by archaeologists in the late 1940s and has since proved very useful. Magnetic methods of prospecting detect buried features by locating the magnetic disturbances they cause. These were introduced in 1957-58 and use such machines as the proton magnetometer, the proton gradiometer, and the fluxgate gradiometer. Electromagnetic methods have been in use only since 1962. They employ developments of the concepts used in mine detectors. Instruments such as the pulsed-induction meter and the soil-conductivity meter detect magnetic soil anomalies, but only if the features are fairly shallow.

Excavation: Excavation is the surgical aspect of archaeology - it is surgery of the buried landscape and is carried out with all the skilled craftsmanship that has been built up in the last hundred years since Schliemann and Flinders Petrie. Excavations can be classified, from the point of view of their purpose, as planned, rescue, or accidental. Most important excavations are the result of a prepared plan--that is to say, their purpose is to locate buried evidence about an archaeological site. Many are project oriented as, for example, when a scholar studying the life of the pre-Roman, Celtic-speaking Gauls of France may deliberately select a group of hill forts and excavate them, as Sir Mortimer Wheeler did in north-western France in the years before the outbreak of World War II. But many excavations, particularly in the heavily populated areas of central and northern Europe, are done not from choice but from necessity. Gravel digging, clearing the ground for airports, quarrying, road widening and building, the construction of houses, factories, and public buildings frequently threaten the destruction of sites known to contain archaeological remains. Emergency excavations then have to be mounted to rescue whatever knowledge of the past can be obtained before these remains are obliterated forever. Partial destruction of cities in western Europe by bombing during World War II allowed rescue excavations to take place before rebuilding. A temple of Mithras in the City of London, Viking settlements in Dublin and at Århus, Denmark, and the original 6th-century-BC Greek settlement of Massalia (Marseille) were discovered in this way. An extension of the runways at London Airport led to the discovery of a pre-Roman Celtic temple there.

The role of chance in the discovery of archaeological sites and portable finds is considerable. Farmers have often unearthed archaeological finds while ploughing their fields. The famous painted and engraved Upper Palaeolithic cave of Lascaux in southern France was discovered by chance in 1940 when four French schoolboys decided to investigate a hole left by an uprooted tree. They widened a smaller shaft at the base of the hole and jumped through to find themselves in the middle of this remarkable pagan sanctuary. Similarly, the first cache of the Dead Sea Scrolls was discovered in 1947 by a Bedouin looking for a stray animal. These accidental finds often lead to important excavations. At Barnénès, in north Brittany, a contractor building a road got his stone from a neighbouring prehistoric cairn (burial mound) and, in so doing, discovered and partially destroyed a number of prehistoric burial chambers. The French archaeologist P-R Giot was able to halt these depredations and carry out scientific excavations that revealed Barnénès to be one of the most remarkable and interesting prehistoric burial mounds in western Europe.

All forms of archaeological excavation require great skill and careful preparation. Years of training in the field, first as an ordinary digger, then as a site supervisor, with spells of work as recorder, surveyor, and photographer, are required before anyone can organize and direct an excavation himself. Most museums, universities, and government archaeological departments organize training excavations. The very words dig and digging may give the impression to many that excavation is merely a matter of shifting away the soil and subsoil with a spade or shovel; the titles of such admirable and widely read books as Leonard Woolley's Spadework (1953) and Digging Up the Past (1930) and Geoffrey Bibby's Testimony of the Spade (1956) might appear to give credence to that view. Actually, much of the work of excavation is careful work with trowel, penknife, and brush. It is often the recovery of features that are almost indistinguishable from non-archaeological aspects of the buried landscape.
One example of this is the recovery of mud-brick walls in Mesopotamia, another is the tracing of collapsed walls of dry stone slabs in a cairn in stony country in the southwest Midlands of England. Sometimes it is the recovery of features of which only ghost traces remain, like the burnt-out bodies from the buried city of Pompeii, or the strings of a harp that were found among the furnishings of Mesopotamian tombs at Ur.

Because of the damage he may cause by inexperience and haste, the untrained amateur archaeologist often hinders the work of the professional. Amateur archaeology is forbidden in many countries by stringent antiquity laws. At the same time, it is certainly true that non-professionals have made important contributions in many areas of archaeology. Occasionally, an amateur does make an important discovery the further excavation of which can then be taken over by trained professionals. Such was the case at Sutton Hoo in Suffolk in 1939, when work begun by a competent amateur was taken over by a team of experts who were able to uncover a great Anglo-Saxon burial boat and its treasure, without doubt the most remarkable archaeological find ever made in Britain.

There are, of course, many different types of archaeological sites, and there is no one set of precepts and rules that will apply to excavation as a whole. Some sites, such as temples, forts, roads, villages, ancient cities, palaces, and industrial remains, are easily visible on the surface of the ground. Among the most obvious archaeological sites that have yielded spectacular results by excavation are the huge man-made mounds (tells) in the Near East, called in Arabic tilal, and in Turkish tepes or hüyüks. They result from the accumulation of remains caused by centuries of human habitation on one spot. The sites of the ancient cities of Troy and Ur are examples. Another type consists of closed sites such as pyramids, chambered tombs, barrows (burial mounds), sealed caves, and rock shelters. In other cases there are no surface traces, and the outline of suspected structures is revealed only by aerial or geophysical reconnaissance as described above. Finally, there are sites in cliffs and gravel beds, where many Palaeolithic finds have been made.

The wide range of techniques employed by the archaeologist vary in their application to different kinds of sites. The opening of the tomb chamber in an Egyptian pyramid is, for example, a very different operation from the excavation of a tell in Mesopotamia or a barrow grave in western Europe. Some sites are explored provisionally by sampling cuts known as sondages. Large sites are not usually dug out entirely, although a moderate-sized round barrow may be completely moved by excavation. Whatever the site and the extent of the excavation, one element of the technique is common to all digs, namely, the use of the greatest care in the actual surgery and in the recording of what is found by word, diagram, survey, and photography. To a certain extent all excavation is destruction, and the total excavation of a site subsequently engulfed by a housing estate or gravel digging is total destruction. This is why the archaeologist's field notes and his published report become primary archaeological documents. They are not themselves, strictly speaking, archaeological facts, they are the excavator's interpretation of what he saw, or thought he saw, but this is the nearest the discipline can ever get to archaeological facts as established by excavation. The really great excavators leave such a fine record of their digs that subsequent archaeologists can re-create and reinterpret what they saw and found. To delay publishing the results of an excavation within a reasonable time is a serious fault from the point of view of archaeological method. An excavation is not complete until the printed report is available to the world. Often the publication of the report takes as long as, or much longer than, the actual work in the field.

When a site like the Palace of Minos at Knossos or the city of Harappa in Pakistan has been excavated, and the excavations are over, the excavator and the antiquities service of the country concerned have to face the problem of what to do with the excavated structures. Should they be covered in again, or should they be preserved for posterity, and if preserved, what degree of conservation and restoration is permissible? This is the same kind of problem that arises in connection with the removal of antiquities from their homeland to foreign museums, and there is no generally accepted answer to it. These problems remain to beset archaeology: should Sir Arthur Evans have reconstructed the Palace of Minos at Knossos? Should the art treasures of ancient Greece and Egypt, now in western European museums, be returned? There is no simple, straightforward, overall answer to these difficult questions.

Underwater archaeology: Underwater archaeology is a branch of reconnaissance and excavation that has been developed only during the 20th century. It involves the same techniques of observation, discovery, and recording that are the basis of archaeology on land, but adapted to the special conditions of working underwater. It is obvious that no archaeologist working on submarine sites can get far unless he is trained as a diver. Helmeted sponge divers have made most of the important archaeological discoveries in the Mediterranean. The French scientist Jacques-Yves Cousteau developed the self-contained breathing apparatus known as the scuba, of which the most commonly used type is the aqualung. Cousteau's work at Le Grand Congloué near Marseille was a pioneer underwater excavation, as was the work of the Americans Peter Throckmorton and George Bass off the coast of southern Turkey. In 1958 Throckmorton found a graveyard of ancient ships at Yassi Ada and then discovered the oldest shipwreck ever recorded, at Cape Gelidonya--a Bronze Age shipwreck of the 14th century BC. George Bass of the University of Pennsylvania worked on a Byzantine wreck at Yassi Ada from 1961 onward, developing the mapping of wrecks photogrammetrically with stereo-photographs and using a two-man submarine, the "Asherah," launched in 1964. The "Asherah" was the first submarine ever built for archaeological investigation.

Interpretation

Excavation often seems to the general public the main and certainly the most glamorous aspect of archaeology, but fieldwork and excavation represent only a part of the archaeologist's work. The other part is the interpretation in cultural and historical contexts of the facts established--by chance, by fieldwork, and by digging--about the material remains of man's past. This task of interpretation has five main aspects.

Classification and analysis: The first concern is the accurate and exact description of all the artefacts concerned. Classification and description are essential to all archaeological work, and, as in botany and zoology, the first requirement is a good and objective taxonomy.

Second, there is a need for interpretive analysis of the material from which artefacts were made. This is something that the archaeologist himself is rarely equipped to do, so he has to rely on colleagues specializing in geology, petrology (analysis of rocks), and metallurgy. In the early 1920s, H.H. Thomas of the Geological Survey of Great Britain was able to show that stones used in the construction of Stonehenge had come from the Prescelly Mountains of north Pembrokeshire. He established as a fact of prehistory that over 4,000 years ago these large stones had been transported 200 miles from west Wales to Salisbury Plain. Detailed petrological analysis of the material of Neolithic polished stone axes have enabled archaeologists to establish the location of prehistoric axe factories and trade routes. It is also now possible, entirely on a petrological basis, to study the prehistoric distribution of obsidian (a volcanic glass used to make primitive tools).

In the third place, the archaeologist, having dealt with the material of his artefacts by classification and taxonomy, and with its physical nature by petrology and metallurgy, turns to the remaining information he can get from his colleagues in the natural sciences. These tell him the environmental conditions in which the people he is studying lived; he now sees his material remains not as isolated artefacts but in the context of their original environments.

Dating: Having analysed his discoveries according to their form, material, and biological association, the archaeologist then comes to the all-important problem of dating. Many material remains of man's past have no dating problem: they may be, like coins, or most coins, self-dating, or they may be dated by man-made dates in written records. But the great and difficult part of the archaeologist's work is dating material remains that are not themselves dated. This can be done in one of three ways. Sometimes an object from another culture, the date of which is known (e.g., in the case of pottery, by its style), is found at a previously undated site. Then, using the relative dating principle the archaeologist reasons that the material found with the imported object is contemporary with it. Conversely, an object from an undated culture may be found at a site whose date is known. Thus non-literate communities can be dated by their contact with literate ones. This technique is known as cross dating. It was first developed by Sir Flinders Petrie when he dated Palestinian and early Greek (Aegean) sites by reference to Egyptian ones. Much of the prehistoric chronology of Europe in the Neolithic, Bronze, and Early Iron ages is based on cross dating with the ancient Near East.

Aside from cross dating, the archaeologist faced with material in a site having no literate chronological evidence of its own has two other ways of dating his material. The first is relative, the second absolute. Relative dating merely means the relation of the date of anything found to the date of other things found in its immediate neighbourhood. As has already been described, this method also plays a part in cross dating. Stratigraphy is the essence of relative dating. The archaeologist observes the accumulation of deposits in a gravel pit, a peat bog, in the construction of a barrow, or in accumulated settlements in a tell, and, like the geologists who introduced the principles of stratigraphy in the late 18th and early 19th centuries, he can see the succession of layers in the site and can then establish the chronology of different levels of layers relative to each other. In the excavation of a great tell like Ur or Troy the relative chronology of the various levels of occupation is the first thing to be established. Some archaeologists, even until quite recent times, have mistakenly supposed that depth below ground level is itself an indication of antiquity. But even in properly observed and recorded stratigraphic levels there is often doubt, and the question arises: are all the artefacts and human remains found in the same level contemporary? Is it possible that there could have been later intrusions that have been difficult to distinguish in the field? The analysis of the fluorine content of bones has been very helpful here. Recognised as a valuable technique by French scientists in the 19th century, it was developed in England by K.P. Oakley in the 1950s. If bones in apparently the same geological or archaeological level have markedly different fluorine content, then it is clear that there must be interference--for example, by a later burial, or by deliberate planting of faked remains, as happened in the case of the Piltdown "Man" hoax in England.

Absolute man-made chronology based on king lists and records in Egypt and Mesopotamia goes back only 5,000 years. For a long time archaeologists searched for an absolute chronology that went beyond this and could turn their relative chronologies into absolute dates. Clay-varve counting seemed to provide the first answer to this need for a nonhuman absolute chronology. Called geochronology by Baron Gerard De Geer, its Swedish inventor, this method was based on counting the thin layers of clay left behind by the melting glaciers when the European Ice Age came to an end. This gave a chronology of about 18,000 years--three times as long as the man-made chronology based on Egyptian and Mesopotamian king lists. Thus, absolute dates could be established for artefacts from the Late Palaeolithic Period, the whole of the Mesolithic Period, or Middle Stone Age, and much of the Early Neolithic Period.

Dendrochronology: the dating of trees by counting their growth rings, was first developed for archaeological purposes by an American, A.E. Douglass. The application of this method to archaeology depends, obviously, on the use in antiquity of old datable trees in the construction of houses and buildings. It has been possible by dendrochronology to date prehistoric American sites as far back as the 3rd and 4th centuries BC.

The greatest revolution in prehistoric archaeology occurred in 1948, when Willard F. Libby, at the University of Chicago, developed the process of radioactive carbon dating. In this method, the activity of radioactive carbon (carbon-14) present in bones, wood, or ash found in archaeological sites is measured. Because the rate at which this activity decreases in time is known, the approximate age of the material can be determined by comparing it to carbon-14 activity in presently living organic matter. There have been problems and uncertainties about the application of the radioactive carbon method, but, although it is less than perfect, it has given archaeology a new and absolute chronology that goes back 40,000 years. Following the revolutionary discovery of radioactive carbon dating, other physical techniques of absolute dating were developed, among them potassium-argon dating and dating by thermo luminescence. Potassium-argon dating has made it possible to establish that the earliest remains of man and his artefacts in East Africa go back at least 2,000,000 years, and probably further.

Historical judgments: The last and most important task of the archaeologist is to transmute his interpretation of the material remains he studies into historical judgments. When he is dealing with medieval and modern history he is often doing no more than adding to knowledge already available from documentary sources: but even so his contribution is often of great importance; for example, in relation to the growth and development of towns and the study of deserted medieval villages. When he is dealing with ancient history and prehistory, he is making a contribution of the greatest importance and often one that is more important than that of purely literary and epigraphical sources. For the prehistoric period, which now appears to stretch from 2,000,000 years ago to about 3000 BC, archaeological evidence is the only source of knowledge about human activities. But prehistoric remains have always been the most difficult to interpret, precisely because there are no written records to aid in the task. Now, with exact dating techniques at his disposal, the prehistorian is becoming more like the historical archaeologist and is concerned with the periodisation and the historical contexts of his finds.

Based on the entry for Archaeology in the Encyclopaedia Britannica (www.eb.com)