As decorated objects must be conveyed by man, the means for their dispersal and the barriers which militate against it are the same as those which operate on human migrations; but there is one difference. Where men go we may assume that they carry their artistic efforts and proclivities with them, but decorated objects may be carried further than the actual distance covered by the manufacturer, or even than the recognised middleman or trader.

This brings us to a very important aspect of the subject, and that is the question of trade-routes. Trade-routes are culture-routes, and in order to appreciate the history of culture it is necessary to know the directions in which it flowed. Until we have a more complete knowledge of the ancient trade-routes of Europe we cannot recover the history of pre-historic Europe. The information for this is being rapidly accumulated, and for a summary of our information I would refer the reader to Mr. George Coffey’s “Origins of Pre-Historic Ornament in Ireland.”[206] I would support my position with the following quotations from Count Goblet d’Alviella:—

“Whatever the similarity of form, and even of meaning, may be between two symbolic figures of different origin, it is proper, ere we assert their relationship, to show the probability, or at least the possibility, of international relations which would have served as a vehicle for transport. This point once set at rest, it remains to be seen who was the giver and who the receiver.[207]

“Whether we start from Japan, from Greece, from India, or even from Lybia, from Etruria, or from Gaul, we always arrive, after many halting-places, at two great centres of artistic diffusion, partially irreducible as regards one another, Egypt and Chaldæa—with this difference, that, towards the eighth century before our era, Mesopotamia took lessons from Egypt, whilst Egypt learnt little of any country.[208] Not only did symbols follow the same paths as purely ornamental schemes, but they were also transmitted in the same manner, at the same periods, and in nearly the same proportion. Concerning symbols as well as artistic products, we everywhere find, by the side of aboriginal types, the deposit of a powerful current which has its more or less distant origin in the symbolism of the banks of the Euphrates, or the Nile. In a word, the two classes of importations are joined together to such a degree that in writing the history of art we write to a great extent the history of symbols, or, at least, of their migrations.”[209]

These quotations from Count Goblet d’Alviella enunciate the right method of studying symbols. He points out, as I have again and again insisted for patterns, that mere resemblance must not be mistaken for identity; before two similar symbols in different countries can be regarded as being the same symbol, it must be proved that there has been direct or indirect intercourse between those countries. Hence the primary importance of the study of trade routes, for these are also culture routes, and patterns and symbols are the flotsam and jetsam of the influences that flow along them.

We may then recognise several main influences which may make for the distribution of designs—(1) the swarmings of peoples; (2) the establishment of organised or adventitious colonies; (3) the inroads of armies; (4) a general drift which is so slight as to be scarcely appreciable; and (5) trade, which usually proceeds along definite routes, and it is these that armies also generally follow.

A word of caution is necessary in dealing with trade-routes. Whereas the decorated objects pass along them and are distributed far and wide, it does not always necessarily follow that the ornamentation itself is naturalised. It is probable that in many cases a certain style of decoration is associated with a particular kind of object, and it might not occur to people to transfer that decorative style to other objects, or at all events the process would doubtless be slow.

One very good reason is that the indigenous objects are already decorated, a type of ornamentation is associated with a type of object and the feeling of expectancy demands for its satisfaction that this shall continue to be the case.

Again, we know that the majority of peoples do not appreciate new designs or patterns. They know nothing about them, they have no associations with them, they take no interest in them. In other words, it may take a long time for an exotic to become naturalised.

An example of this occurs in British New Guinea. The great annual trading voyages between the Motu and the Gulf tribes have not, so far as I am aware, had the least influence on the art of the two peoples; neither in technique nor designs have I seen any object which indicated that a borrowing had taken place. I consider this a strong argument in favour of the value of art in ethnological inquiries.