To account for such a character of wear, there seems no need of going so far afield as among the Eskimos, or any other semi-civilized or savage people, to seek for analogies on which to base a conclusion—how far satisfactory it must be left to others to judge. Among the primary necessities of man (who has been defined as a cooking animal) is that of fire. It is no doubt a question difficult of solution whether our primitive predecessors were acquainted with any more ready means of producing it than |313| by friction of two pieces of wood, especially at a time when there is reason to suppose they were unacquainted with the existence of iron as a metal. I have, however, already mentioned[1415] that for the purpose of producing sparks, pyrites is as effective as iron, and was indeed in use among the Romans. Now the lower beds of our English chalk are prolific of pyrites, though not to the same extent as the upper beds are of flint; and it is not impossible that the use of a hammer-stone of pyrites, in order to form some instrument of flint, gave rise to the discovery of that method of producing fire, the invention of which the old myth attributed to Pyrodes, the son of Cilix. When exposed upon or near the surface of the ground, pyrites is very liable to decomposition, and even if occurring with ancient interments it would be very likely to be disregarded. This may account for the paucity of the notices of its discovery. Some, however, exist, and I have already mentioned[1416] instances where nodules of pyrites have been discovered on the Continent in association with worked flints, both of Neolithic and Palæolithic age.