We have now given accounts of the literature which contains the earliest records of the people of the North. Let us pause and study for a while its archæology, which will throw considerable light also on its inhabitants and their customs. It is now generally recognised by archæologists that all people who have advanced to a certain degree of civilisation have passed through three periods of development, which according to the material of which their implements, weapons, and utensils were made, have been named the _stone_, the _bronze_, and the _iron_ age. We have very abundant evidence that the people of the North passed through these three stages, and indeed had reached the iron age before they came within the ken of history. Beginning with the stone age, let us see what we can learn of the civilisation of the North from the various articles which were in use during the three stages. The finds in the North have been classified under the name “_grave_,” “_bog_,” and “_earth_” _finds_; that is, objects found in graves, bogs, or in the ground. In the latter case they are often hidden under stones, in obedience to the injunctions of Odin. Those of the iron age are found as far as 69° North latitude. The custom of burying different objects with the dead, and also that of throwing objects and weapons into springs or bogs, or of hiding them in the ground, has helped in a most remarkable manner to give us an idea of the industries and daily life of the people there at a remote period. In the earliest age the use of metal was unknown, the weapons were made of stone, horn, and bone,[110] and towards the close of this age pottery was made. The first traces of man in some parts of the present Scandinavia are the _kjökkenmöddinger_ (kitchen refuse heaps), consisting of oyster and mussel shells, bones of fish, birds, and mammals, such as the deer, bear, boar, beaver, seal, ure-ox, wolf, fox, &c., &c., with remains of clay vessels. Among and near these heaps of refuse are found a great number of rude implements and weapons made of flint, bone, horn, and broken flint chips, also fireplaces made of a few stones roughly put together, thus showing that the inhabitants lived in a very primitive state. No graves of the earliest period of the stone age have thus far been found in the North. Towards the latter part of this age we see a great improvement in the making of weapons and tools; the latter were beautifully polished, and graceful in form. Domestic animals had also been introduced, as shown by the bones of cattle, horses, sheep, pigs, and dogs, that have been found in the graves. Beads of amber and bone were worn as ornaments. The graves of the stone age discovered in the present Scandinavia and on the islands and shores of the Baltic may be classified in four groups: the _cromlech_ or _dolmen_; the _passage_ or _gallery graves_; the _free-standing stone coffins_; and the _stone coffins covered by a mound_.[111]