The people of the Bronze age introduced a higher civilisation into the world than their predecessors of the Stone ages. There appears to be a great overlap between the Neolithic, Bronze, and Iron ages of Central and Northern Europe, and the historic periods of the Eastern countries bordering on the Mediterranean. We have evidence that great periods of time must have marked the epochs of the prehistoric ages, and that the Bronze age, like the Stone and Iron ages, began at different times in different countries. The tribes who brought with them the age of Bronze into Europe composed the Celtic van of the Aryan race. The earliest productions of this period were the simple wedges resembling flat stone axes, the sides of which are slightly thickened to form ridges or flanges; the centres are also raised, which produces a ridge to prevent the head from going in too far in the handle; in some the flanges are much developed, and have also a loop cast on the side for the purpose of tying it on to the haft. Some are made with a socket and loop; these have been called “Paalstabs,” and have a flat chisel-like shape (Figs. 28, 30). [Illustration: Fig. 28.] [Illustration: Fig. 29.] [Illustration: Fig. 30.] Figs. 28 to 30.—Bronze and Paalstabs. (From _Danish Arts_.) [Illustration: Fig. 31.] [Illustration: Fig. 32.] [Illustration: Fig. 33.] [Illustration: Fig. 34.] Figs. 31 to 34.—Bronze Axes, Paalstabs, and Moulds. (From _Danish Arts_.) [Illustration: Fig. 35.] [Illustration: Fig. 36.] [Illustration: Fig. 37.] [Illustration: Fig. 38.] Figs. 35 to 38.—Bronze Swords and Spear-Head. (From _Danish Arts_.) [Illustration: Figs. 39 and 40.—Bronze Button for Sword Belt. (From _Danish Arts_.) ] These earlier implements are often made of pure copper. Bronze is a mixture of copper and tin, generally from two to four per cent. of tin, and is consequently harder than copper. Knives, hammers, gouges, sickles, daggers, spears, swords, shields, many kinds of vessels, and articles of personal adornment made in bronze, belong to the earlier time of the Bronze period, and similar articles were made in this material in the prehistoric Bronze ages all over the known world (Figs. 35 to 40). An interesting object is a breast-plate, belonging to this early Bronze period; it is decorated with zigzags in bands, and a well-arranged scheme of spiral ornamentation (Fig. 41). Urns of earthenware, sometimes decorated with zigzags and sacred signs, have been found in graves. These urns contained ashes of the dead (Figs. 43, 44). [Illustration: Fig. 41.—Breast-plate, with Spiral Ornaments. (From _Danish Arts_.)] Many of the bronze implements and other articles have been found in tombs, in caves in great quantities, both finished and unfinished, in “Kitchen Middens,” or refuse heaps, in river-beds, and in bogs. [Illustration: Fig. 42.] [Illustration: Fig. 43.] [Illustration: Fig. 44.]