aces. This is particularly evident in the boat figures (Helskog 1985,1988). Many of the panels at Alta thus do not appear to be extensively chronologically mixed, although there is no method that can guarantee a ‘chronological homogeneity’.
The figures at the panel of Storsteinen were made on the top surface (20.4 m above sea level) of a four- meter high, flat-topped boulder on the steep slope of a glacial frontal deposit. They contain a mixture of manners of depiction, covering a longer time span than at any other panel. The reason for dies is that in front of this boulder there are no lower rock surfaces where new figures could be made as the waterline receded — this boulder is unique in this respect in Alta. Storsteinen appears to have been used and engraved for 1500- 2000 years, as long as the boulder was connected to the shoreline. A radiocarbon date from deposits covering figures 20 m above sea level on the rock surface indicates that a part of the panel was covered by peat when surfaces at 8.5 m-11 m above sea level were engraved. The obvious point here is that a panel which represents a relatively short period of time will provide clearer rock art units and will be easier to tie to other aspects of the prehistoric record than one with figures covering a long period of rime. The bigger question is: are changes in rock art content and manner of depiction over time indicative of changing meanings?
In contrast to the rock engravings, the environment associated with the rock paintings changed less. The painted figures are found on vertical surfaces in dark caves and shelters. Inside the caves, all along the Norwegian coast, the changes were minimal, while the outside environment changed with the shore displacement and climatic changes. In caves and shelters, paintings of human figures dominate numerically (Bjerck 1995); in many caves only images of humans are painted. To the east, in Finland, no engravings have yet been found and the paintings, all on open cliffs above water (Kivikäs 1995), are more diverse than those in the caves and shelters of Norway.
Part of the explanation for the differences between paintings and engravings is to be found in the rituals associated with the location of the panels, and possibly with the surfaces themselves. The painted figures in caves (inside) and shelters (inside-outside) are all on vertical surfaces, while the engraved figures are always on the outside, on a variety of surfaces but seldom on a totally vertical surface. The engravings, with the absolute largest number of classes and types of figures, are embedded into the rock in the open, and were, judging from variety, sheer numbers and diversity of surfaces, associated with a larger diversity of rituals and stories than the paintings.
The surfaces on which modern painters normally work are flat with a vertical or horizontal dimension, while the makers of rock engravings worked on surfaces of which no two are identical. These surfaces vary in size, topography, gradient and orientation. Added to this, the light would have been constantly changing. A large surface has room for more figures than small surfaces. Uneven and undulating surfaces with cracks or fissures can be utilised differently to flat, even and unbroken surfaces. Steep surfaces can be used to convey different messages to horizontal surfaces, and so on. But, we have also to keep in mind that different surfaces could be used in a similar way and could carry similar meanings.
Modern painters have learnt to convey a sense of depth of field by using shading, foreshortening, perspective, and so on. The rock artists at Alta and Zalavruga, and those from all parts of northern Europe, do not use these techniques in their images and compositions. Yet the engravings themselves are three-dimensional. Also, the integration of features in the rock surfaces provides a similar sense of depth and of three-dimensionality as when one is looking at places in a landscape. The integration of surface features might indeed make the total representation a three-dimensional one. Further di